chore(peerjs): Clean up ignored files

.gitignore

@@ -18,4 +18,5 @@ npm-debug.log
 test/output
 dist
 .tscache
-test/public
+test/public
+

dist/peer.js

@@ -1,7989 +0,0 @@
-(function(){function r(e,n,t){function o(i,f){if(!n[i]){if(!e[i]){var c="function"==typeof require&&require;if(!f&&c)return c(i,!0);if(u)return u(i,!0);var a=new Error("Cannot find module '"+i+"'");throw a.code="MODULE_NOT_FOUND",a}var p=n[i]={exports:{}};e[i][0].call(p.exports,function(r){var n=e[i][1][r];return o(n||r)},p,p.exports,r,e,n,t)}return n[i].exports}for(var u="function"==typeof require&&require,i=0;i<t.length;i++)o(t[i]);return o}return r})()({1:[function(require,module,exports){
-require('webrtc-adapter');
-module.exports.RTCSessionDescription = window.RTCSessionDescription ||
-    window.mozRTCSessionDescription;
-module.exports.RTCPeerConnection = window.RTCPeerConnection ||
-    window.mozRTCPeerConnection || window.webkitRTCPeerConnection;
-module.exports.RTCIceCandidate = window.RTCIceCandidate ||
-    window.mozRTCIceCandidate;
-
-},{"webrtc-adapter":16}],2:[function(require,module,exports){
-var util = require('./util');
-var EventEmitter = require('eventemitter3');
-var Negotiator = require('./negotiator');
-var Reliable = require('reliable');
-function DataConnection(peer, provider, options) {
-    if (!(this instanceof DataConnection))
-        return new DataConnection(peer, provider, options);
-    EventEmitter.call(this);
-    this.options = util.extend({
-        serialization: 'binary',
-        reliable: false
-    }, options);
-    this.open = false;
-    this.type = 'data';
-    this.peer = peer;
-    this.provider = provider;
-    this.id = this.options.connectionId || DataConnection._idPrefix + util.randomToken();
-    this.label = this.options.label || this.id;
-    this.metadata = this.options.metadata;
-    this.serialization = this.options.serialization;
-    this.reliable = this.options.reliable;
-    this._buffer = [];
-    this._buffering = false;
-    this.bufferSize = 0;
-    this._chunkedData = {};
-    if (this.options._payload) {
-        this._peerBrowser = this.options._payload.browser;
-    }
-    Negotiator.startConnection(this, this.options._payload || {
-        originator: true
-    });
-}
-util.inherits(DataConnection, EventEmitter);
-DataConnection._idPrefix = 'dc_';
-DataConnection.prototype.initialize = function (dc) {
-    this._dc = this.dataChannel = dc;
-    this._configureDataChannel();
-};
-DataConnection.prototype._configureDataChannel = function () {
-    var self = this;
-    if (util.supports.sctp) {
-        this._dc.binaryType = 'arraybuffer';
-    }
-    this._dc.onopen = function () {
-        util.log('Data channel connection success');
-        self.open = true;
-        self.emit('open');
-    };
-    if (!util.supports.sctp && this.reliable) {
-        this._reliable = new Reliable(this._dc, util.debug);
-    }
-    if (this._reliable) {
-        this._reliable.onmessage = function (msg) {
-            self.emit('data', msg);
-        };
-    }
-    else {
-        this._dc.onmessage = function (e) {
-            self._handleDataMessage(e);
-        };
-    }
-    this._dc.onclose = function (e) {
-        util.log('DataChannel closed for:', self.peer);
-        self.close();
-    };
-};
-DataConnection.prototype._handleDataMessage = function (e) {
-    var self = this;
-    var data = e.data;
-    var datatype = data.constructor;
-    if (this.serialization === 'binary' || this.serialization === 'binary-utf8') {
-        if (datatype === Blob) {
-            util.blobToArrayBuffer(data, function (ab) {
-                data = util.unpack(ab);
-                self.emit('data', data);
-            });
-            return;
-        }
-        else if (datatype === ArrayBuffer) {
-            data = util.unpack(data);
-        }
-        else if (datatype === String) {
-            var ab = util.binaryStringToArrayBuffer(data);
-            data = util.unpack(ab);
-        }
-    }
-    else if (this.serialization === 'json') {
-        data = JSON.parse(data);
-    }
-    if (data.__peerData) {
-        var id = data.__peerData;
-        var chunkInfo = this._chunkedData[id] || { data: [], count: 0, total: data.total };
-        chunkInfo.data[data.n] = data.data;
-        chunkInfo.count += 1;
-        if (chunkInfo.total === chunkInfo.count) {
-            delete this._chunkedData[id];
-            data = new Blob(chunkInfo.data);
-            this._handleDataMessage({ data: data });
-        }
-        this._chunkedData[id] = chunkInfo;
-        return;
-    }
-    this.emit('data', data);
-};
-DataConnection.prototype.close = function () {
-    if (!this.open) {
-        return;
-    }
-    this.open = false;
-    Negotiator.cleanup(this);
-    this.emit('close');
-};
-DataConnection.prototype.send = function (data, chunked) {
-    if (!this.open) {
-        this.emit('error', new Error('Connection is not open. You should listen for the `open` event before sending messages.'));
-        return;
-    }
-    if (this._reliable) {
-        this._reliable.send(data);
-        return;
-    }
-    var self = this;
-    if (this.serialization === 'json') {
-        this._bufferedSend(JSON.stringify(data));
-    }
-    else if (this.serialization === 'binary' || this.serialization === 'binary-utf8') {
-        var blob = util.pack(data);
-        var needsChunking = util.chunkedBrowsers[this._peerBrowser] || util.chunkedBrowsers[util.browser];
-        if (needsChunking && !chunked && blob.size > util.chunkedMTU) {
-            this._sendChunks(blob);
-            return;
-        }
-        if (!util.supports.sctp) {
-            util.blobToBinaryString(blob, function (str) {
-                self._bufferedSend(str);
-            });
-        }
-        else if (!util.supports.binaryBlob) {
-            util.blobToArrayBuffer(blob, function (ab) {
-                self._bufferedSend(ab);
-            });
-        }
-        else {
-            this._bufferedSend(blob);
-        }
-    }
-    else {
-        this._bufferedSend(data);
-    }
-};
-DataConnection.prototype._bufferedSend = function (msg) {
-    if (this._buffering || !this._trySend(msg)) {
-        this._buffer.push(msg);
-        this.bufferSize = this._buffer.length;
-    }
-};
-DataConnection.prototype._trySend = function (msg) {
-    try {
-        this._dc.send(msg);
-    }
-    catch (e) {
-        this._buffering = true;
-        var self = this;
-        setTimeout(function () {
-            self._buffering = false;
-            self._tryBuffer();
-        }, 100);
-        return false;
-    }
-    return true;
-};
-DataConnection.prototype._tryBuffer = function () {
-    if (this._buffer.length === 0) {
-        return;
-    }
-    var msg = this._buffer[0];
-    if (this._trySend(msg)) {
-        this._buffer.shift();
-        this.bufferSize = this._buffer.length;
-        this._tryBuffer();
-    }
-};
-DataConnection.prototype._sendChunks = function (blob) {
-    var blobs = util.chunk(blob);
-    for (var i = 0, ii = blobs.length; i < ii; i += 1) {
-        var blob = blobs[i];
-        this.send(blob, true);
-    }
-};
-DataConnection.prototype.handleMessage = function (message) {
-    var payload = message.payload;
-    switch (message.type) {
-        case 'ANSWER':
-            this._peerBrowser = payload.browser;
-            Negotiator.handleSDP(message.type, this, payload.sdp);
-            break;
-        case 'CANDIDATE':
-            Negotiator.handleCandidate(this, payload.candidate);
-            break;
-        default:
-            util.warn('Unrecognized message type:', message.type, 'from peer:', this.peer);
-            break;
-    }
-};
-module.exports = DataConnection;
-
-},{"./negotiator":5,"./util":8,"eventemitter3":9,"reliable":12}],3:[function(require,module,exports){
-window.Socket = require("./socket");
-window.MediaConnection = require("./mediaconnection");
-window.DataConnection = require("./dataconnection");
-window.Peer = require("./peer");
-window.RTCPeerConnection = require("./adapter").RTCPeerConnection;
-window.RTCSessionDescription = require("./adapter").RTCSessionDescription;
-window.RTCIceCandidate = require("./adapter").RTCIceCandidate;
-window.Negotiator = require("./negotiator");
-window.util = require("./util");
-window.BinaryPack = require("js-binarypack");
-
-},{"./adapter":1,"./dataconnection":2,"./mediaconnection":4,"./negotiator":5,"./peer":6,"./socket":7,"./util":8,"js-binarypack":10}],4:[function(require,module,exports){
-var util = require('./util');
-var EventEmitter = require('eventemitter3');
-var Negotiator = require('./negotiator');
-function MediaConnection(peer, provider, options) {
-    if (!(this instanceof MediaConnection))
-        return new MediaConnection(peer, provider, options);
-    EventEmitter.call(this);
-    this.options = util.extend({}, options);
-    this.open = false;
-    this.type = 'media';
-    this.peer = peer;
-    this.provider = provider;
-    this.metadata = this.options.metadata;
-    this.localStream = this.options._stream;
-    this.id = this.options.connectionId || MediaConnection._idPrefix + util.randomToken();
-    if (this.localStream) {
-        Negotiator.startConnection(this, { _stream: this.localStream, originator: true });
-    }
-}
-;
-util.inherits(MediaConnection, EventEmitter);
-MediaConnection._idPrefix = 'mc_';
-MediaConnection.prototype.addStream = function (remoteStream) {
-    util.log('Receiving stream', remoteStream);
-    this.remoteStream = remoteStream;
-    this.emit('stream', remoteStream);
-};
-MediaConnection.prototype.handleMessage = function (message) {
-    var payload = message.payload;
-    switch (message.type) {
-        case 'ANSWER':
-            Negotiator.handleSDP(message.type, this, payload.sdp);
-            this.open = true;
-            break;
-        case 'CANDIDATE':
-            Negotiator.handleCandidate(this, payload.candidate);
-            break;
-        default:
-            util.warn('Unrecognized message type:', message.type, 'from peer:', this.peer);
-            break;
-    }
-};
-MediaConnection.prototype.answer = function (stream) {
-    if (this.localStream) {
-        util.warn('Local stream already exists on this MediaConnection. Are you answering a call twice?');
-        return;
-    }
-    this.options._payload._stream = stream;
-    this.localStream = stream;
-    Negotiator.startConnection(this, this.options._payload);
-    var messages = this.provider._getMessages(this.id);
-    for (var i = 0, ii = messages.length; i < ii; i += 1) {
-        this.handleMessage(messages[i]);
-    }
-    this.open = true;
-};
-MediaConnection.prototype.close = function () {
-    if (!this.open) {
-        return;
-    }
-    this.open = false;
-    Negotiator.cleanup(this);
-    this.emit('close');
-};
-module.exports = MediaConnection;
-
-},{"./negotiator":5,"./util":8,"eventemitter3":9}],5:[function(require,module,exports){
-var util = require("./util");
-var RTCPeerConnection = require("./adapter").RTCPeerConnection;
-var RTCSessionDescription = require("./adapter").RTCSessionDescription;
-var RTCIceCandidate = require("./adapter").RTCIceCandidate;
-var Negotiator = {
-    pcs: {
-        data: {},
-        media: {}
-    },
-    queue: []
-};
-Negotiator._idPrefix = "pc_";
-Negotiator.startConnection = function (connection, options) {
-    var pc = Negotiator._getPeerConnection(connection, options);
-    connection.pc = connection.peerConnection = pc;
-    if (connection.type === "media" && options._stream) {
-        pc.addStream(options._stream);
-    }
-    if (options.originator) {
-        if (connection.type === "data") {
-            var config = {};
-            if (!util.supports.sctp) {
-                config = { reliable: options.reliable };
-            }
-            var dc = pc.createDataChannel(connection.label, config);
-            connection.initialize(dc);
-        }
-        Negotiator._makeOffer(connection);
-    }
-    else {
-        Negotiator.handleSDP("OFFER", connection, options.sdp);
-    }
-};
-Negotiator._getPeerConnection = function (connection, options) {
-    if (!Negotiator.pcs[connection.type]) {
-        util.error(connection.type +
-            " is not a valid connection type. Maybe you overrode the `type` property somewhere.");
-    }
-    if (!Negotiator.pcs[connection.type][connection.peer]) {
-        Negotiator.pcs[connection.type][connection.peer] = {};
-    }
-    var peerConnections = Negotiator.pcs[connection.type][connection.peer];
-    var pc;
-    if (options.pc) {
-        pc = Negotiator.pcs[connection.type][connection.peer][options.pc];
-    }
-    if (!pc || pc.signalingState !== "stable") {
-        pc = Negotiator._startPeerConnection(connection);
-    }
-    return pc;
-};
-Negotiator._startPeerConnection = function (connection) {
-    util.log("Creating RTCPeerConnection.");
-    var id = Negotiator._idPrefix + util.randomToken();
-    var optional = {};
-    if (connection.type === "data" && !util.supports.sctp) {
-        optional = { optional: [{ RtpDataChannels: true }] };
-    }
-    else if (connection.type === "media") {
-        optional = { optional: [{ DtlsSrtpKeyAgreement: true }] };
-    }
-    var pc = new RTCPeerConnection(connection.provider.options.config, optional);
-    Negotiator.pcs[connection.type][connection.peer][id] = pc;
-    Negotiator._setupListeners(connection, pc, id);
-    return pc;
-};
-Negotiator._setupListeners = function (connection, pc, pc_id) {
-    var peerId = connection.peer;
-    var connectionId = connection.id;
-    var provider = connection.provider;
-    util.log("Listening for ICE candidates.");
-    pc.onicecandidate = function (evt) {
-        if (evt.candidate) {
-            util.log("Received ICE candidates for:", connection.peer);
-            provider.socket.send({
-                type: "CANDIDATE",
-                payload: {
-                    candidate: evt.candidate,
-                    type: connection.type,
-                    connectionId: connection.id
-                },
-                dst: peerId
-            });
-        }
-    };
-    pc.oniceconnectionstatechange = function () {
-        switch (pc.iceConnectionState) {
-            case "failed":
-                util.log("iceConnectionState is disconnected, closing connections to " + peerId);
-                connection.emit("error", new Error("Negotiation of connection to " + peerId + " failed."));
-                connection.close();
-                break;
-            case "disconnected":
-                util.log("iceConnectionState is disconnected, closing connections to " + peerId);
-                connection.close();
-                break;
-            case "completed":
-                pc.onicecandidate = util.noop;
-                break;
-        }
-    };
-    pc.onicechange = pc.oniceconnectionstatechange;
-    util.log("Listening for data channel");
-    pc.ondatachannel = function (evt) {
-        util.log("Received data channel");
-        var dc = evt.channel;
-        var connection = provider.getConnection(peerId, connectionId);
-        connection.initialize(dc);
-    };
-    util.log("Listening for remote stream");
-    pc.ontrack = function (evt) {
-        util.log("Received remote stream");
-        var stream = evt.streams[0];
-        var connection = provider.getConnection(peerId, connectionId);
-        if (connection.type === "media") {
-            connection.addStream(stream);
-        }
-    };
-};
-Negotiator.cleanup = function (connection) {
-    util.log("Cleaning up PeerConnection to " + connection.peer);
-    var pc = connection.pc;
-    if (!!pc &&
-        ((pc.readyState && pc.readyState !== "closed") ||
-            pc.signalingState !== "closed")) {
-        pc.close();
-        connection.pc = null;
-    }
-};
-Negotiator._makeOffer = function (connection) {
-    var pc = connection.pc;
-    pc.createOffer(function (offer) {
-        util.log("Created offer.");
-        if (!util.supports.sctp &&
-            connection.type === "data" &&
-            connection.reliable) {
-            offer.sdp = Reliable.higherBandwidthSDP(offer.sdp);
-        }
-        pc.setLocalDescription(offer, function () {
-            util.log("Set localDescription: offer", "for:", connection.peer);
-            connection.provider.socket.send({
-                type: "OFFER",
-                payload: {
-                    sdp: offer,
-                    type: connection.type,
-                    label: connection.label,
-                    connectionId: connection.id,
-                    reliable: connection.reliable,
-                    serialization: connection.serialization,
-                    metadata: connection.metadata,
-                    browser: util.browser
-                },
-                dst: connection.peer
-            });
-        }, function (err) {
-            if (err !=
-                "OperationError: Failed to set local offer sdp: Called in wrong state: kHaveRemoteOffer") {
-                connection.provider.emitError("webrtc", err);
-                util.log("Failed to setLocalDescription, ", err);
-            }
-        });
-    }, function (err) {
-        connection.provider.emitError("webrtc", err);
-        util.log("Failed to createOffer, ", err);
-    }, connection.options.constraints);
-};
-Negotiator._makeAnswer = function (connection) {
-    var pc = connection.pc;
-    pc.createAnswer(function (answer) {
-        util.log("Created answer.");
-        if (!util.supports.sctp &&
-            connection.type === "data" &&
-            connection.reliable) {
-            answer.sdp = Reliable.higherBandwidthSDP(answer.sdp);
-        }
-        pc.setLocalDescription(answer, function () {
-            util.log("Set localDescription: answer", "for:", connection.peer);
-            connection.provider.socket.send({
-                type: "ANSWER",
-                payload: {
-                    sdp: answer,
-                    type: connection.type,
-                    connectionId: connection.id,
-                    browser: util.browser
-                },
-                dst: connection.peer
-            });
-        }, function (err) {
-            connection.provider.emitError("webrtc", err);
-            util.log("Failed to setLocalDescription, ", err);
-        });
-    }, function (err) {
-        connection.provider.emitError("webrtc", err);
-        util.log("Failed to create answer, ", err);
-    });
-};
-Negotiator.handleSDP = function (type, connection, sdp) {
-    sdp = new RTCSessionDescription(sdp);
-    var pc = connection.pc;
-    util.log("Setting remote description", sdp);
-    pc.setRemoteDescription(sdp, function () {
-        util.log("Set remoteDescription:", type, "for:", connection.peer);
-        if (type === "OFFER") {
-            Negotiator._makeAnswer(connection);
-        }
-    }, function (err) {
-        connection.provider.emitError("webrtc", err);
-        util.log("Failed to setRemoteDescription, ", err);
-    });
-};
-Negotiator.handleCandidate = function (connection, ice) {
-    var candidate = ice.candidate;
-    var sdpMLineIndex = ice.sdpMLineIndex;
-    connection.pc.addIceCandidate(new RTCIceCandidate({
-        sdpMLineIndex: sdpMLineIndex,
-        candidate: candidate
-    }));
-    util.log("Added ICE candidate for:", connection.peer);
-};
-module.exports = Negotiator;
-
-},{"./adapter":1,"./util":8}],6:[function(require,module,exports){
-var util = require("./util");
-var EventEmitter = require("eventemitter3");
-var Socket = require("./socket");
-var MediaConnection = require("./mediaconnection");
-var DataConnection = require("./dataconnection");
-function Peer(id, options) {
-    if (!(this instanceof Peer))
-        return new Peer(id, options);
-    EventEmitter.call(this);
-    if (id && id.constructor == Object) {
-        options = id;
-        id = undefined;
-    }
-    else if (id) {
-        id = id.toString();
-    }
-    options = util.extend({
-        debug: 0,
-        host: util.CLOUD_HOST,
-        port: util.CLOUD_PORT,
-        path: "/",
-        token: util.randomToken(),
-        config: util.defaultConfig
-    }, options);
-    options.key = "peerjs";
-    this.options = options;
-    if (options.host === "/") {
-        options.host = window.location.hostname;
-    }
-    if (options.path[0] !== "/") {
-        options.path = "/" + options.path;
-    }
-    if (options.path[options.path.length - 1] !== "/") {
-        options.path += "/";
-    }
-    if (options.secure === undefined && options.host !== util.CLOUD_HOST) {
-        options.secure = util.isSecure();
-    }
-    else if (options.host == util.CLOUD_HOST) {
-        options.secure = true;
-    }
-    if (options.logFunction) {
-        util.setLogFunction(options.logFunction);
-    }
-    util.setLogLevel(options.debug);
-    if (!util.supports.audioVideo && !util.supports.data) {
-        this._delayedAbort("browser-incompatible", "The current browser does not support WebRTC");
-        return;
-    }
-    if (!util.validateId(id)) {
-        this._delayedAbort("invalid-id", 'ID "' + id + '" is invalid');
-        return;
-    }
-    this.destroyed = false;
-    this.disconnected = false;
-    this.open = false;
-    this.connections = {};
-    this._lostMessages = {};
-    this._initializeServerConnection();
-    if (id) {
-        this._initialize(id);
-    }
-    else {
-        this._retrieveId();
-    }
-}
-util.inherits(Peer, EventEmitter);
-Peer.prototype._initializeServerConnection = function () {
-    var self = this;
-    this.socket = new Socket(this.options.secure, this.options.host, this.options.port, this.options.path, this.options.key, this.options.wsport);
-    this.socket.on("message", function (data) {
-        self._handleMessage(data);
-    });
-    this.socket.on("error", function (error) {
-        self._abort("socket-error", error);
-    });
-    this.socket.on("disconnected", function () {
-        if (!self.disconnected) {
-            self.emitError("network", "Lost connection to server.");
-            self.disconnect();
-        }
-    });
-    this.socket.on("close", function () {
-        if (!self.disconnected) {
-            self._abort("socket-closed", "Underlying socket is already closed.");
-        }
-    });
-};
-Peer.prototype._retrieveId = function (cb) {
-    var self = this;
-    var http = new XMLHttpRequest();
-    var protocol = this.options.secure ? "https://" : "http://";
-    var url = protocol +
-        this.options.host +
-        ":" +
-        this.options.port +
-        this.options.path +
-        this.options.key +
-        "/id";
-    var queryString = "?ts=" + new Date().getTime() + "" + Math.random();
-    url += queryString;
-    http.open("get", url, true);
-    http.onerror = function (e) {
-        util.error("Error retrieving ID", e);
-        var pathError = "";
-        if (self.options.path === "/" && self.options.host !== util.CLOUD_HOST) {
-            pathError =
-                " If you passed in a `path` to your self-hosted PeerServer, " +
-                    "you'll also need to pass in that same path when creating a new " +
-                    "Peer.";
-        }
-        self._abort("server-error", "Could not get an ID from the server." + pathError);
-    };
-    http.onreadystatechange = function () {
-        if (http.readyState !== 4) {
-            return;
-        }
-        if (http.status !== 200) {
-            http.onerror();
-            return;
-        }
-        self._initialize(http.responseText);
-    };
-    http.send(null);
-};
-Peer.prototype._initialize = function (id) {
-    this.id = id;
-    this.socket.start(this.id, this.options.token);
-};
-Peer.prototype._handleMessage = function (message) {
-    var type = message.type;
-    var payload = message.payload;
-    var peer = message.src;
-    var connection;
-    switch (type) {
-        case "OPEN":
-            this.emit("open", this.id);
-            this.open = true;
-            break;
-        case "ERROR":
-            this._abort("server-error", payload.msg);
-            break;
-        case "ID-TAKEN":
-            this._abort("unavailable-id", "ID `" + this.id + "` is taken");
-            break;
-        case "INVALID-KEY":
-            this._abort("invalid-key", 'API KEY "' + this.options.key + '" is invalid');
-            break;
-        case "LEAVE":
-            util.log("Received leave message from", peer);
-            this._cleanupPeer(peer);
-            break;
-        case "EXPIRE":
-            this.emitError("peer-unavailable", "Could not connect to peer " + peer);
-            break;
-        case "OFFER":
-            var connectionId = payload.connectionId;
-            connection = this.getConnection(peer, connectionId);
-            if (connection) {
-                connection.close();
-                util.warn("Offer received for existing Connection ID:", connectionId);
-            }
-            if (payload.type === "media") {
-                connection = new MediaConnection(peer, this, {
-                    connectionId: connectionId,
-                    _payload: payload,
-                    metadata: payload.metadata
-                });
-                this._addConnection(peer, connection);
-                this.emit("call", connection);
-            }
-            else if (payload.type === "data") {
-                connection = new DataConnection(peer, this, {
-                    connectionId: connectionId,
-                    _payload: payload,
-                    metadata: payload.metadata,
-                    label: payload.label,
-                    serialization: payload.serialization,
-                    reliable: payload.reliable
-                });
-                this._addConnection(peer, connection);
-                this.emit("connection", connection);
-            }
-            else {
-                util.warn("Received malformed connection type:", payload.type);
-                return;
-            }
-            var messages = this._getMessages(connectionId);
-            for (var i = 0, ii = messages.length; i < ii; i += 1) {
-                connection.handleMessage(messages[i]);
-            }
-            break;
-        default:
-            if (!payload) {
-                util.warn("You received a malformed message from " + peer + " of type " + type);
-                return;
-            }
-            var id = payload.connectionId;
-            connection = this.getConnection(peer, id);
-            if (connection && connection.pc) {
-                connection.handleMessage(message);
-            }
-            else if (id) {
-                this._storeMessage(id, message);
-            }
-            else {
-                util.warn("You received an unrecognized message:", message);
-            }
-            break;
-    }
-};
-Peer.prototype._storeMessage = function (connectionId, message) {
-    if (!this._lostMessages[connectionId]) {
-        this._lostMessages[connectionId] = [];
-    }
-    this._lostMessages[connectionId].push(message);
-};
-Peer.prototype._getMessages = function (connectionId) {
-    var messages = this._lostMessages[connectionId];
-    if (messages) {
-        delete this._lostMessages[connectionId];
-        return messages;
-    }
-    else {
-        return [];
-    }
-};
-Peer.prototype.connect = function (peer, options) {
-    if (this.disconnected) {
-        util.warn("You cannot connect to a new Peer because you called " +
-            ".disconnect() on this Peer and ended your connection with the " +
-            "server. You can create a new Peer to reconnect, or call reconnect " +
-            "on this peer if you believe its ID to still be available.");
-        this.emitError("disconnected", "Cannot connect to new Peer after disconnecting from server.");
-        return;
-    }
-    var connection = new DataConnection(peer, this, options);
-    this._addConnection(peer, connection);
-    return connection;
-};
-Peer.prototype.call = function (peer, stream, options) {
-    if (this.disconnected) {
-        util.warn("You cannot connect to a new Peer because you called " +
-            ".disconnect() on this Peer and ended your connection with the " +
-            "server. You can create a new Peer to reconnect.");
-        this.emitError("disconnected", "Cannot connect to new Peer after disconnecting from server.");
-        return;
-    }
-    if (!stream) {
-        util.error("To call a peer, you must provide a stream from your browser's `getUserMedia`.");
-        return;
-    }
-    options = options || {};
-    options._stream = stream;
-    var call = new MediaConnection(peer, this, options);
-    this._addConnection(peer, call);
-    return call;
-};
-Peer.prototype._addConnection = function (peer, connection) {
-    if (!this.connections[peer]) {
-        this.connections[peer] = [];
-    }
-    this.connections[peer].push(connection);
-};
-Peer.prototype.getConnection = function (peer, id) {
-    var connections = this.connections[peer];
-    if (!connections) {
-        return null;
-    }
-    for (var i = 0, ii = connections.length; i < ii; i++) {
-        if (connections[i].id === id) {
-            return connections[i];
-        }
-    }
-    return null;
-};
-Peer.prototype._delayedAbort = function (type, message) {
-    var self = this;
-    util.setZeroTimeout(function () {
-        self._abort(type, message);
-    });
-};
-Peer.prototype._abort = function (type, message) {
-    util.error("Aborting!");
-    if (!this._lastServerId) {
-        this.destroy();
-    }
-    else {
-        this.disconnect();
-    }
-    this.emitError(type, message);
-};
-Peer.prototype.emitError = function (type, err) {
-    util.error("Error:", err);
-    if (typeof err === "string") {
-        err = new Error(err);
-    }
-    err.type = type;
-    this.emit("error", err);
-};
-Peer.prototype.destroy = function () {
-    if (!this.destroyed) {
-        this._cleanup();
-        this.disconnect();
-        this.destroyed = true;
-    }
-};
-Peer.prototype._cleanup = function () {
-    if (this.connections) {
-        var peers = Object.keys(this.connections);
-        for (var i = 0, ii = peers.length; i < ii; i++) {
-            this._cleanupPeer(peers[i]);
-        }
-    }
-    this.emit("close");
-};
-Peer.prototype._cleanupPeer = function (peer) {
-    var connections = this.connections[peer];
-    for (var j = 0, jj = connections.length; j < jj; j += 1) {
-        connections[j].close();
-    }
-};
-Peer.prototype.disconnect = function () {
-    var self = this;
-    util.setZeroTimeout(function () {
-        if (!self.disconnected) {
-            self.disconnected = true;
-            self.open = false;
-            if (self.socket) {
-                self.socket.close();
-            }
-            self.emit("disconnected", self.id);
-            self._lastServerId = self.id;
-            self.id = null;
-        }
-    });
-};
-Peer.prototype.reconnect = function () {
-    if (this.disconnected && !this.destroyed) {
-        util.log("Attempting reconnection to server with ID " + this._lastServerId);
-        this.disconnected = false;
-        this._initializeServerConnection();
-        this._initialize(this._lastServerId);
-    }
-    else if (this.destroyed) {
-        throw new Error("This peer cannot reconnect to the server. It has already been destroyed.");
-    }
-    else if (!this.disconnected && !this.open) {
-        util.error("In a hurry? We're still trying to make the initial connection!");
-    }
-    else {
-        throw new Error("Peer " +
-            this.id +
-            " cannot reconnect because it is not disconnected from the server!");
-    }
-};
-Peer.prototype.listAllPeers = function (cb) {
-    cb = cb || function () { };
-    var self = this;
-    var http = new XMLHttpRequest();
-    var protocol = this.options.secure ? "https://" : "http://";
-    var url = protocol +
-        this.options.host +
-        ":" +
-        this.options.port +
-        this.options.path +
-        this.options.key +
-        "/peers";
-    var queryString = "?ts=" + new Date().getTime() + "" + Math.random();
-    url += queryString;
-    http.open("get", url, true);
-    http.onerror = function (e) {
-        self._abort("server-error", "Could not get peers from the server.");
-        cb([]);
-    };
-    http.onreadystatechange = function () {
-        if (http.readyState !== 4) {
-            return;
-        }
-        if (http.status === 401) {
-            var helpfulError = "";
-            if (self.options.host !== util.CLOUD_HOST) {
-                helpfulError =
-                    "It looks like you're using the cloud server. You can email " +
-                        "team@peerjs.com to enable peer listing for your API key.";
-            }
-            else {
-                helpfulError =
-                    "You need to enable `allow_discovery` on your self-hosted " +
-                        "PeerServer to use this feature.";
-            }
-            cb([]);
-            throw new Error("It doesn't look like you have permission to list peers IDs. " +
-                helpfulError);
-        }
-        else if (http.status !== 200) {
-            cb([]);
-        }
-        else {
-            cb(JSON.parse(http.responseText));
-        }
-    };
-    http.send(null);
-};
-module.exports = Peer;
-
-},{"./dataconnection":2,"./mediaconnection":4,"./socket":7,"./util":8,"eventemitter3":9}],7:[function(require,module,exports){
-var util = require('./util');
-var EventEmitter = require('eventemitter3');
-function Socket(secure, host, port, path, key, wsport) {
-    if (!(this instanceof Socket))
-        return new Socket(secure, host, port, path, key, wsport);
-    wsport = wsport || port;
-    EventEmitter.call(this);
-    this.disconnected = false;
-    this._queue = [];
-    var httpProtocol = secure ? 'https://' : 'http://';
-    var wsProtocol = secure ? 'wss://' : 'ws://';
-    this._httpUrl = httpProtocol + host + ':' + port + path + key;
-    this._wsUrl = wsProtocol + host + ':' + wsport + path + 'peerjs?key=' + key;
-}
-util.inherits(Socket, EventEmitter);
-Socket.prototype.start = function (id, token) {
-    this.id = id;
-    this._httpUrl += '/' + id + '/' + token;
-    this._wsUrl += '&id=' + id + '&token=' + token;
-    this._startXhrStream();
-    this._startWebSocket();
-};
-Socket.prototype._startWebSocket = function (id) {
-    var self = this;
-    if (this._socket) {
-        return;
-    }
-    this._socket = new WebSocket(this._wsUrl);
-    this._socket.onmessage = function (event) {
-        try {
-            var data = JSON.parse(event.data);
-        }
-        catch (e) {
-            util.log('Invalid server message', event.data);
-            return;
-        }
-        self.emit('message', data);
-    };
-    this._socket.onclose = function (event) {
-        util.log('Socket closed.');
-        self.disconnected = true;
-        self.emit('disconnected');
-    };
-    this._socket.onopen = function () {
-        if (self._timeout) {
-            clearTimeout(self._timeout);
-            setTimeout(function () {
-                self._http.abort();
-                self._http = null;
-            }, 5000);
-        }
-        self._sendQueuedMessages();
-        util.log('Socket open');
-    };
-};
-Socket.prototype._startXhrStream = function (n) {
-    try {
-        var self = this;
-        this._http = new XMLHttpRequest();
-        this._http._index = 1;
-        this._http._streamIndex = n || 0;
-        this._http.open('post', this._httpUrl + '/id?i=' + this._http._streamIndex, true);
-        this._http.onerror = function () {
-            clearTimeout(self._timeout);
-            self.emit('disconnected');
-        };
-        this._http.onreadystatechange = function () {
-            if (this.readyState == 2 && this.old) {
-                this.old.abort();
-                delete this.old;
-            }
-            else if (this.readyState > 2 && this.status === 200 && this.responseText) {
-                self._handleStream(this);
-            }
-        };
-        this._http.send(null);
-        this._setHTTPTimeout();
-    }
-    catch (e) {
-        util.log('XMLHttpRequest not available; defaulting to WebSockets');
-    }
-};
-Socket.prototype._handleStream = function (http) {
-    var messages = http.responseText.split('\n');
-    if (http._buffer) {
-        while (http._buffer.length > 0) {
-            var index = http._buffer.shift();
-            var bufferedMessage = messages[index];
-            try {
-                bufferedMessage = JSON.parse(bufferedMessage);
-            }
-            catch (e) {
-                http._buffer.shift(index);
-                break;
-            }
-            this.emit('message', bufferedMessage);
-        }
-    }
-    var message = messages[http._index];
-    if (message) {
-        http._index += 1;
-        if (http._index === messages.length) {
-            if (!http._buffer) {
-                http._buffer = [];
-            }
-            http._buffer.push(http._index - 1);
-        }
-        else {
-            try {
-                message = JSON.parse(message);
-            }
-            catch (e) {
-                util.log('Invalid server message', message);
-                return;
-            }
-            this.emit('message', message);
-        }
-    }
-};
-Socket.prototype._setHTTPTimeout = function () {
-    var self = this;
-    this._timeout = setTimeout(function () {
-        var old = self._http;
-        if (!self._wsOpen()) {
-            self._startXhrStream(old._streamIndex + 1);
-            self._http.old = old;
-        }
-        else {
-            old.abort();
-        }
-    }, 25000);
-};
-Socket.prototype._wsOpen = function () {
-    return this._socket && this._socket.readyState == 1;
-};
-Socket.prototype._sendQueuedMessages = function () {
-    for (var i = 0, ii = this._queue.length; i < ii; i += 1) {
-        this.send(this._queue[i]);
-    }
-};
-Socket.prototype.send = function (data) {
-    if (this.disconnected) {
-        return;
-    }
-    if (!this.id) {
-        this._queue.push(data);
-        return;
-    }
-    if (!data.type) {
-        this.emit('error', 'Invalid message');
-        return;
-    }
-    var message = JSON.stringify(data);
-    if (this._wsOpen()) {
-        this._socket.send(message);
-    }
-    else {
-        var http = new XMLHttpRequest();
-        var url = this._httpUrl + '/' + data.type.toLowerCase();
-        http.open('post', url, true);
-        http.setRequestHeader('Content-Type', 'application/json');
-        http.send(message);
-    }
-};
-Socket.prototype.close = function () {
-    if (!this.disconnected && this._wsOpen()) {
-        this._socket.close();
-        this.disconnected = true;
-    }
-};
-module.exports = Socket;
-
-},{"./util":8,"eventemitter3":9}],8:[function(require,module,exports){
-var defaultConfig = { 'iceServers': [{ 'urls': 'stun:stun.l.google.com:19302' }] };
-var dataCount = 1;
-var BinaryPack = require("js-binarypack");
-var RTCPeerConnection = require("./adapter").RTCPeerConnection;
-var util = {
-    noop: function () { },
-    CLOUD_HOST: "0.peerjs.com",
-    CLOUD_PORT: 443,
-    chunkedBrowsers: { Chrome: 1 },
-    chunkedMTU: 16300,
-    logLevel: 0,
-    setLogLevel: function (level) {
-        var debugLevel = parseInt(level, 10);
-        if (!isNaN(parseInt(level, 10))) {
-            util.logLevel = debugLevel;
-        }
-        else {
-            util.logLevel = level ? 3 : 0;
-        }
-        util.log = util.warn = util.error = util.noop;
-        if (util.logLevel > 0) {
-            util.error = util._printWith("ERROR");
-        }
-        if (util.logLevel > 1) {
-            util.warn = util._printWith("WARNING");
-        }
-        if (util.logLevel > 2) {
-            util.log = util._print;
-        }
-    },
-    setLogFunction: function (fn) {
-        if (fn.constructor !== Function) {
-            util.warn("The log function you passed in is not a function. Defaulting to regular logs.");
-        }
-        else {
-            util._print = fn;
-        }
-    },
-    _printWith: function (prefix) {
-        return function () {
-            var copy = Array.prototype.slice.call(arguments);
-            copy.unshift(prefix);
-            util._print.apply(util, copy);
-        };
-    },
-    _print: function () {
-        var err = false;
-        var copy = Array.prototype.slice.call(arguments);
-        copy.unshift("PeerJS: ");
-        for (var i = 0, l = copy.length; i < l; i++) {
-            if (copy[i] instanceof Error) {
-                copy[i] = "(" + copy[i].name + ") " + copy[i].message;
-                err = true;
-            }
-        }
-        err ? console.error.apply(console, copy) : console.log.apply(console, copy);
-    },
-    defaultConfig: defaultConfig,
-    browser: (function () {
-        if (window.mozRTCPeerConnection) {
-            return "Firefox";
-        }
-        else if (window.webkitRTCPeerConnection) {
-            return "Chrome";
-        }
-        else if (window.RTCPeerConnection) {
-            return "Supported";
-        }
-        else {
-            return "Unsupported";
-        }
-    })(),
-    supports: (function () {
-        if (typeof RTCPeerConnection === "undefined") {
-            return {};
-        }
-        var data = true;
-        var audioVideo = true;
-        var binaryBlob = false;
-        var sctp = false;
-        var onnegotiationneeded = !!window.webkitRTCPeerConnection;
-        var pc, dc;
-        try {
-            pc = new RTCPeerConnection(defaultConfig, {
-                optional: [{ RtpDataChannels: true }]
-            });
-        }
-        catch (e) {
-            data = false;
-            audioVideo = false;
-        }
-        if (data) {
-            try {
-                dc = pc.createDataChannel("_PEERJSTEST");
-            }
-            catch (e) {
-                data = false;
-            }
-        }
-        if (data) {
-            try {
-                dc.binaryType = "blob";
-                binaryBlob = true;
-            }
-            catch (e) { }
-            var reliablePC = new RTCPeerConnection(defaultConfig, {});
-            try {
-                var reliableDC = reliablePC.createDataChannel("_PEERJSRELIABLETEST", {});
-                sctp = reliableDC.reliable;
-            }
-            catch (e) { }
-            reliablePC.close();
-        }
-        if (audioVideo) {
-            audioVideo = !!pc.addStream;
-        }
-        if (pc) {
-            pc.close();
-        }
-        return {
-            audioVideo: audioVideo,
-            data: data,
-            binaryBlob: binaryBlob,
-            binary: sctp,
-            reliable: sctp,
-            sctp: sctp,
-            onnegotiationneeded: onnegotiationneeded
-        };
-    })(),
-    validateId: function (id) {
-        return !id || /^[A-Za-z0-9]+(?:[ _-][A-Za-z0-9]+)*$/.exec(id);
-    },
-    validateKey: function (key) {
-        return !key || /^[A-Za-z0-9]+(?:[ _-][A-Za-z0-9]+)*$/.exec(key);
-    },
-    debug: false,
-    inherits: function (ctor, superCtor) {
-        ctor.super_ = superCtor;
-        ctor.prototype = Object.create(superCtor.prototype, {
-            constructor: {
-                value: ctor,
-                enumerable: false,
-                writable: true,
-                configurable: true
-            }
-        });
-    },
-    extend: function (dest, source) {
-        for (var key in source) {
-            if (source.hasOwnProperty(key)) {
-                dest[key] = source[key];
-            }
-        }
-        return dest;
-    },
-    pack: BinaryPack.pack,
-    unpack: BinaryPack.unpack,
-    log: function () {
-        if (util.debug) {
-            var err = false;
-            var copy = Array.prototype.slice.call(arguments);
-            copy.unshift("PeerJS: ");
-            for (var i = 0, l = copy.length; i < l; i++) {
-                if (copy[i] instanceof Error) {
-                    copy[i] = "(" + copy[i].name + ") " + copy[i].message;
-                    err = true;
-                }
-            }
-            err
-                ? console.error.apply(console, copy)
-                : console.log.apply(console, copy);
-        }
-    },
-    setZeroTimeout: (function (global) {
-        var timeouts = [];
-        var messageName = "zero-timeout-message";
-        function setZeroTimeoutPostMessage(fn) {
-            timeouts.push(fn);
-            global.postMessage(messageName, "*");
-        }
-        function handleMessage(event) {
-            if (event.source == global && event.data == messageName) {
-                if (event.stopPropagation) {
-                    event.stopPropagation();
-                }
-                if (timeouts.length) {
-                    timeouts.shift()();
-                }
-            }
-        }
-        if (global.addEventListener) {
-            global.addEventListener("message", handleMessage, true);
-        }
-        else if (global.attachEvent) {
-            global.attachEvent("onmessage", handleMessage);
-        }
-        return setZeroTimeoutPostMessage;
-    })(window),
-    chunk: function (bl) {
-        var chunks = [];
-        var size = bl.size;
-        var start = (index = 0);
-        var total = Math.ceil(size / util.chunkedMTU);
-        while (start < size) {
-            var end = Math.min(size, start + util.chunkedMTU);
-            var b = bl.slice(start, end);
-            var chunk = {
-                __peerData: dataCount,
-                n: index,
-                data: b,
-                total: total
-            };
-            chunks.push(chunk);
-            start = end;
-            index += 1;
-        }
-        dataCount += 1;
-        return chunks;
-    },
-    blobToArrayBuffer: function (blob, cb) {
-        var fr = new FileReader();
-        fr.onload = function (evt) {
-            cb(evt.target.result);
-        };
-        fr.readAsArrayBuffer(blob);
-    },
-    blobToBinaryString: function (blob, cb) {
-        var fr = new FileReader();
-        fr.onload = function (evt) {
-            cb(evt.target.result);
-        };
-        fr.readAsBinaryString(blob);
-    },
-    binaryStringToArrayBuffer: function (binary) {
-        var byteArray = new Uint8Array(binary.length);
-        for (var i = 0; i < binary.length; i++) {
-            byteArray[i] = binary.charCodeAt(i) & 0xff;
-        }
-        return byteArray.buffer;
-    },
-    randomToken: function () {
-        return Math.random()
-            .toString(36)
-            .substr(2);
-    },
-    isSecure: function () {
-        return location.protocol === "https:";
-    }
-};
-module.exports = util;
-
-},{"./adapter":1,"js-binarypack":10}],9:[function(require,module,exports){
-'use strict';
-
-/**
- * Representation of a single EventEmitter function.
- *
- * @param {Function} fn Event handler to be called.
- * @param {Mixed} context Context for function execution.
- * @param {Boolean} once Only emit once
- * @api private
- */
-function EE(fn, context, once) {
-  this.fn = fn;
-  this.context = context;
-  this.once = once || false;
-}
-
-/**
- * Minimal EventEmitter interface that is molded against the Node.js
- * EventEmitter interface.
- *
- * @constructor
- * @api public
- */
-function EventEmitter() { /* Nothing to set */ }
-
-/**
- * Holds the assigned EventEmitters by name.
- *
- * @type {Object}
- * @private
- */
-EventEmitter.prototype._events = undefined;
-
-/**
- * Return a list of assigned event listeners.
- *
- * @param {String} event The events that should be listed.
- * @returns {Array}
- * @api public
- */
-EventEmitter.prototype.listeners = function listeners(event) {
-  if (!this._events || !this._events[event]) return [];
-  if (this._events[event].fn) return [this._events[event].fn];
-
-  for (var i = 0, l = this._events[event].length, ee = new Array(l); i < l; i++) {
-    ee[i] = this._events[event][i].fn;
-  }
-
-  return ee;
-};
-
-/**
- * Emit an event to all registered event listeners.
- *
- * @param {String} event The name of the event.
- * @returns {Boolean} Indication if we've emitted an event.
- * @api public
- */
-EventEmitter.prototype.emit = function emit(event, a1, a2, a3, a4, a5) {
-  if (!this._events || !this._events[event]) return false;
-
-  var listeners = this._events[event]
-    , len = arguments.length
-    , args
-    , i;
-
-  if ('function' === typeof listeners.fn) {
-    if (listeners.once) this.removeListener(event, listeners.fn, true);
-
-    switch (len) {
-      case 1: return listeners.fn.call(listeners.context), true;
-      case 2: return listeners.fn.call(listeners.context, a1), true;
-      case 3: return listeners.fn.call(listeners.context, a1, a2), true;
-      case 4: return listeners.fn.call(listeners.context, a1, a2, a3), true;
-      case 5: return listeners.fn.call(listeners.context, a1, a2, a3, a4), true;
-      case 6: return listeners.fn.call(listeners.context, a1, a2, a3, a4, a5), true;
-    }
-
-    for (i = 1, args = new Array(len -1); i < len; i++) {
-      args[i - 1] = arguments[i];
-    }
-
-    listeners.fn.apply(listeners.context, args);
-  } else {
-    var length = listeners.length
-      , j;
-
-    for (i = 0; i < length; i++) {
-      if (listeners[i].once) this.removeListener(event, listeners[i].fn, true);
-
-      switch (len) {
-        case 1: listeners[i].fn.call(listeners[i].context); break;
-        case 2: listeners[i].fn.call(listeners[i].context, a1); break;
-        case 3: listeners[i].fn.call(listeners[i].context, a1, a2); break;
-        default:
-          if (!args) for (j = 1, args = new Array(len -1); j < len; j++) {
-            args[j - 1] = arguments[j];
-          }
-
-          listeners[i].fn.apply(listeners[i].context, args);
-      }
-    }
-  }
-
-  return true;
-};
-
-/**
- * Register a new EventListener for the given event.
- *
- * @param {String} event Name of the event.
- * @param {Functon} fn Callback function.
- * @param {Mixed} context The context of the function.
- * @api public
- */
-EventEmitter.prototype.on = function on(event, fn, context) {
-  var listener = new EE(fn, context || this);
-
-  if (!this._events) this._events = {};
-  if (!this._events[event]) this._events[event] = listener;
-  else {
-    if (!this._events[event].fn) this._events[event].push(listener);
-    else this._events[event] = [
-      this._events[event], listener
-    ];
-  }
-
-  return this;
-};
-
-/**
- * Add an EventListener that's only called once.
- *
- * @param {String} event Name of the event.
- * @param {Function} fn Callback function.
- * @param {Mixed} context The context of the function.
- * @api public
- */
-EventEmitter.prototype.once = function once(event, fn, context) {
-  var listener = new EE(fn, context || this, true);
-
-  if (!this._events) this._events = {};
-  if (!this._events[event]) this._events[event] = listener;
-  else {
-    if (!this._events[event].fn) this._events[event].push(listener);
-    else this._events[event] = [
-      this._events[event], listener
-    ];
-  }
-
-  return this;
-};
-
-/**
- * Remove event listeners.
- *
- * @param {String} event The event we want to remove.
- * @param {Function} fn The listener that we need to find.
- * @param {Boolean} once Only remove once listeners.
- * @api public
- */
-EventEmitter.prototype.removeListener = function removeListener(event, fn, once) {
-  if (!this._events || !this._events[event]) return this;
-
-  var listeners = this._events[event]
-    , events = [];
-
-  if (fn) {
-    if (listeners.fn && (listeners.fn !== fn || (once && !listeners.once))) {
-      events.push(listeners);
-    }
-    if (!listeners.fn) for (var i = 0, length = listeners.length; i < length; i++) {
-      if (listeners[i].fn !== fn || (once && !listeners[i].once)) {
-        events.push(listeners[i]);
-      }
-    }
-  }
-
-  //
-  // Reset the array, or remove it completely if we have no more listeners.
-  //
-  if (events.length) {
-    this._events[event] = events.length === 1 ? events[0] : events;
-  } else {
-    delete this._events[event];
-  }
-
-  return this;
-};
-
-/**
- * Remove all listeners or only the listeners for the specified event.
- *
- * @param {String} event The event want to remove all listeners for.
- * @api public
- */
-EventEmitter.prototype.removeAllListeners = function removeAllListeners(event) {
-  if (!this._events) return this;
-
-  if (event) delete this._events[event];
-  else this._events = {};
-
-  return this;
-};
-
-//
-// Alias methods names because people roll like that.
-//
-EventEmitter.prototype.off = EventEmitter.prototype.removeListener;
-EventEmitter.prototype.addListener = EventEmitter.prototype.on;
-
-//
-// This function doesn't apply anymore.
-//
-EventEmitter.prototype.setMaxListeners = function setMaxListeners() {
-  return this;
-};
-
-//
-// Expose the module.
-//
-EventEmitter.EventEmitter = EventEmitter;
-EventEmitter.EventEmitter2 = EventEmitter;
-EventEmitter.EventEmitter3 = EventEmitter;
-
-//
-// Expose the module.
-//
-module.exports = EventEmitter;
-
-},{}],10:[function(require,module,exports){
-var BufferBuilder = require('./bufferbuilder').BufferBuilder;
-var binaryFeatures = require('./bufferbuilder').binaryFeatures;
-
-var BinaryPack = {
-  unpack: function(data){
-    var unpacker = new Unpacker(data);
-    return unpacker.unpack();
-  },
-  pack: function(data){
-    var packer = new Packer();
-    packer.pack(data);
-    var buffer = packer.getBuffer();
-    return buffer;
-  }
-};
-
-module.exports = BinaryPack;
-
-function Unpacker (data){
-  // Data is ArrayBuffer
-  this.index = 0;
-  this.dataBuffer = data;
-  this.dataView = new Uint8Array(this.dataBuffer);
-  this.length = this.dataBuffer.byteLength;
-}
-
-Unpacker.prototype.unpack = function(){
-  var type = this.unpack_uint8();
-  if (type < 0x80){
-    var positive_fixnum = type;
-    return positive_fixnum;
-  } else if ((type ^ 0xe0) < 0x20){
-    var negative_fixnum = (type ^ 0xe0) - 0x20;
-    return negative_fixnum;
-  }
-  var size;
-  if ((size = type ^ 0xa0) <= 0x0f){
-    return this.unpack_raw(size);
-  } else if ((size = type ^ 0xb0) <= 0x0f){
-    return this.unpack_string(size);
-  } else if ((size = type ^ 0x90) <= 0x0f){
-    return this.unpack_array(size);
-  } else if ((size = type ^ 0x80) <= 0x0f){
-    return this.unpack_map(size);
-  }
-  switch(type){
-    case 0xc0:
-      return null;
-    case 0xc1:
-      return undefined;
-    case 0xc2:
-      return false;
-    case 0xc3:
-      return true;
-    case 0xca:
-      return this.unpack_float();
-    case 0xcb:
-      return this.unpack_double();
-    case 0xcc:
-      return this.unpack_uint8();
-    case 0xcd:
-      return this.unpack_uint16();
-    case 0xce:
-      return this.unpack_uint32();
-    case 0xcf:
-      return this.unpack_uint64();
-    case 0xd0:
-      return this.unpack_int8();
-    case 0xd1:
-      return this.unpack_int16();
-    case 0xd2:
-      return this.unpack_int32();
-    case 0xd3:
-      return this.unpack_int64();
-    case 0xd4:
-      return undefined;
-    case 0xd5:
-      return undefined;
-    case 0xd6:
-      return undefined;
-    case 0xd7:
-      return undefined;
-    case 0xd8:
-      size = this.unpack_uint16();
-      return this.unpack_string(size);
-    case 0xd9:
-      size = this.unpack_uint32();
-      return this.unpack_string(size);
-    case 0xda:
-      size = this.unpack_uint16();
-      return this.unpack_raw(size);
-    case 0xdb:
-      size = this.unpack_uint32();
-      return this.unpack_raw(size);
-    case 0xdc:
-      size = this.unpack_uint16();
-      return this.unpack_array(size);
-    case 0xdd:
-      size = this.unpack_uint32();
-      return this.unpack_array(size);
-    case 0xde:
-      size = this.unpack_uint16();
-      return this.unpack_map(size);
-    case 0xdf:
-      size = this.unpack_uint32();
-      return this.unpack_map(size);
-  }
-}
-
-Unpacker.prototype.unpack_uint8 = function(){
-  var byte = this.dataView[this.index] & 0xff;
-  this.index++;
-  return byte;
-};
-
-Unpacker.prototype.unpack_uint16 = function(){
-  var bytes = this.read(2);
-  var uint16 =
-    ((bytes[0] & 0xff) * 256) + (bytes[1] & 0xff);
-  this.index += 2;
-  return uint16;
-}
-
-Unpacker.prototype.unpack_uint32 = function(){
-  var bytes = this.read(4);
-  var uint32 =
-     ((bytes[0]  * 256 +
-       bytes[1]) * 256 +
-       bytes[2]) * 256 +
-       bytes[3];
-  this.index += 4;
-  return uint32;
-}
-
-Unpacker.prototype.unpack_uint64 = function(){
-  var bytes = this.read(8);
-  var uint64 =
-   ((((((bytes[0]  * 256 +
-       bytes[1]) * 256 +
-       bytes[2]) * 256 +
-       bytes[3]) * 256 +
-       bytes[4]) * 256 +
-       bytes[5]) * 256 +
-       bytes[6]) * 256 +
-       bytes[7];
-  this.index += 8;
-  return uint64;
-}
-
-
-Unpacker.prototype.unpack_int8 = function(){
-  var uint8 = this.unpack_uint8();
-  return (uint8 < 0x80 ) ? uint8 : uint8 - (1 << 8);
-};
-
-Unpacker.prototype.unpack_int16 = function(){
-  var uint16 = this.unpack_uint16();
-  return (uint16 < 0x8000 ) ? uint16 : uint16 - (1 << 16);
-}
-
-Unpacker.prototype.unpack_int32 = function(){
-  var uint32 = this.unpack_uint32();
-  return (uint32 < Math.pow(2, 31) ) ? uint32 :
-    uint32 - Math.pow(2, 32);
-}
-
-Unpacker.prototype.unpack_int64 = function(){
-  var uint64 = this.unpack_uint64();
-  return (uint64 < Math.pow(2, 63) ) ? uint64 :
-    uint64 - Math.pow(2, 64);
-}
-
-Unpacker.prototype.unpack_raw = function(size){
-  if ( this.length < this.index + size){
-    throw new Error('BinaryPackFailure: index is out of range'
-      + ' ' + this.index + ' ' + size + ' ' + this.length);
-  }
-  var buf = this.dataBuffer.slice(this.index, this.index + size);
-  this.index += size;
-
-    //buf = util.bufferToString(buf);
-
-  return buf;
-}
-
-Unpacker.prototype.unpack_string = function(size){
-  var bytes = this.read(size);
-  var i = 0, str = '', c, code;
-  while(i < size){
-    c = bytes[i];
-    if ( c < 128){
-      str += String.fromCharCode(c);
-      i++;
-    } else if ((c ^ 0xc0) < 32){
-      code = ((c ^ 0xc0) << 6) | (bytes[i+1] & 63);
-      str += String.fromCharCode(code);
-      i += 2;
-    } else {
-      code = ((c & 15) << 12) | ((bytes[i+1] & 63) << 6) |
-        (bytes[i+2] & 63);
-      str += String.fromCharCode(code);
-      i += 3;
-    }
-  }
-  this.index += size;
-  return str;
-}
-
-Unpacker.prototype.unpack_array = function(size){
-  var objects = new Array(size);
-  for(var i = 0; i < size ; i++){
-    objects[i] = this.unpack();
-  }
-  return objects;
-}
-
-Unpacker.prototype.unpack_map = function(size){
-  var map = {};
-  for(var i = 0; i < size ; i++){
-    var key  = this.unpack();
-    var value = this.unpack();
-    map[key] = value;
-  }
-  return map;
-}
-
-Unpacker.prototype.unpack_float = function(){
-  var uint32 = this.unpack_uint32();
-  var sign = uint32 >> 31;
-  var exp  = ((uint32 >> 23) & 0xff) - 127;
-  var fraction = ( uint32 & 0x7fffff ) | 0x800000;
-  return (sign == 0 ? 1 : -1) *
-    fraction * Math.pow(2, exp - 23);
-}
-
-Unpacker.prototype.unpack_double = function(){
-  var h32 = this.unpack_uint32();
-  var l32 = this.unpack_uint32();
-  var sign = h32 >> 31;
-  var exp  = ((h32 >> 20) & 0x7ff) - 1023;
-  var hfrac = ( h32 & 0xfffff ) | 0x100000;
-  var frac = hfrac * Math.pow(2, exp - 20) +
-    l32   * Math.pow(2, exp - 52);
-  return (sign == 0 ? 1 : -1) * frac;
-}
-
-Unpacker.prototype.read = function(length){
-  var j = this.index;
-  if (j + length <= this.length) {
-    return this.dataView.subarray(j, j + length);
-  } else {
-    throw new Error('BinaryPackFailure: read index out of range');
-  }
-}
-
-function Packer(){
-  this.bufferBuilder = new BufferBuilder();
-}
-
-Packer.prototype.getBuffer = function(){
-  return this.bufferBuilder.getBuffer();
-}
-
-Packer.prototype.pack = function(value){
-  var type = typeof(value);
-  if (type == 'string'){
-    this.pack_string(value);
-  } else if (type == 'number'){
-    if (Math.floor(value) === value){
-      this.pack_integer(value);
-    } else{
-      this.pack_double(value);
-    }
-  } else if (type == 'boolean'){
-    if (value === true){
-      this.bufferBuilder.append(0xc3);
-    } else if (value === false){
-      this.bufferBuilder.append(0xc2);
-    }
-  } else if (type == 'undefined'){
-    this.bufferBuilder.append(0xc0);
-  } else if (type == 'object'){
-    if (value === null){
-      this.bufferBuilder.append(0xc0);
-    } else {
-      var constructor = value.constructor;
-      if (constructor == Array){
-        this.pack_array(value);
-      } else if (constructor == Blob || constructor == File) {
-        this.pack_bin(value);
-      } else if (constructor == ArrayBuffer) {
-        if(binaryFeatures.useArrayBufferView) {
-          this.pack_bin(new Uint8Array(value));
-        } else {
-          this.pack_bin(value);
-        }
-      } else if ('BYTES_PER_ELEMENT' in value){
-        if(binaryFeatures.useArrayBufferView) {
-          this.pack_bin(new Uint8Array(value.buffer));
-        } else {
-          this.pack_bin(value.buffer);
-        }
-      } else if (constructor == Object){
-        this.pack_object(value);
-      } else if (constructor == Date){
-        this.pack_string(value.toString());
-      } else if (typeof value.toBinaryPack == 'function'){
-        this.bufferBuilder.append(value.toBinaryPack());
-      } else {
-        throw new Error('Type "' + constructor.toString() + '" not yet supported');
-      }
-    }
-  } else {
-    throw new Error('Type "' + type + '" not yet supported');
-  }
-  this.bufferBuilder.flush();
-}
-
-
-Packer.prototype.pack_bin = function(blob){
-  var length = blob.length || blob.byteLength || blob.size;
-  if (length <= 0x0f){
-    this.pack_uint8(0xa0 + length);
-  } else if (length <= 0xffff){
-    this.bufferBuilder.append(0xda) ;
-    this.pack_uint16(length);
-  } else if (length <= 0xffffffff){
-    this.bufferBuilder.append(0xdb);
-    this.pack_uint32(length);
-  } else{
-    throw new Error('Invalid length');
-  }
-  this.bufferBuilder.append(blob);
-}
-
-Packer.prototype.pack_string = function(str){
-  var length = utf8Length(str);
-
-  if (length <= 0x0f){
-    this.pack_uint8(0xb0 + length);
-  } else if (length <= 0xffff){
-    this.bufferBuilder.append(0xd8) ;
-    this.pack_uint16(length);
-  } else if (length <= 0xffffffff){
-    this.bufferBuilder.append(0xd9);
-    this.pack_uint32(length);
-  } else{
-    throw new Error('Invalid length');
-  }
-  this.bufferBuilder.append(str);
-}
-
-Packer.prototype.pack_array = function(ary){
-  var length = ary.length;
-  if (length <= 0x0f){
-    this.pack_uint8(0x90 + length);
-  } else if (length <= 0xffff){
-    this.bufferBuilder.append(0xdc)
-    this.pack_uint16(length);
-  } else if (length <= 0xffffffff){
-    this.bufferBuilder.append(0xdd);
-    this.pack_uint32(length);
-  } else{
-    throw new Error('Invalid length');
-  }
-  for(var i = 0; i < length ; i++){
-    this.pack(ary[i]);
-  }
-}
-
-Packer.prototype.pack_integer = function(num){
-  if ( -0x20 <= num && num <= 0x7f){
-    this.bufferBuilder.append(num & 0xff);
-  } else if (0x00 <= num && num <= 0xff){
-    this.bufferBuilder.append(0xcc);
-    this.pack_uint8(num);
-  } else if (-0x80 <= num && num <= 0x7f){
-    this.bufferBuilder.append(0xd0);
-    this.pack_int8(num);
-  } else if ( 0x0000 <= num && num <= 0xffff){
-    this.bufferBuilder.append(0xcd);
-    this.pack_uint16(num);
-  } else if (-0x8000 <= num && num <= 0x7fff){
-    this.bufferBuilder.append(0xd1);
-    this.pack_int16(num);
-  } else if ( 0x00000000 <= num && num <= 0xffffffff){
-    this.bufferBuilder.append(0xce);
-    this.pack_uint32(num);
-  } else if (-0x80000000 <= num && num <= 0x7fffffff){
-    this.bufferBuilder.append(0xd2);
-    this.pack_int32(num);
-  } else if (-0x8000000000000000 <= num && num <= 0x7FFFFFFFFFFFFFFF){
-    this.bufferBuilder.append(0xd3);
-    this.pack_int64(num);
-  } else if (0x0000000000000000 <= num && num <= 0xFFFFFFFFFFFFFFFF){
-    this.bufferBuilder.append(0xcf);
-    this.pack_uint64(num);
-  } else{
-    throw new Error('Invalid integer');
-  }
-}
-
-Packer.prototype.pack_double = function(num){
-  var sign = 0;
-  if (num < 0){
-    sign = 1;
-    num = -num;
-  }
-  var exp  = Math.floor(Math.log(num) / Math.LN2);
-  var frac0 = num / Math.pow(2, exp) - 1;
-  var frac1 = Math.floor(frac0 * Math.pow(2, 52));
-  var b32   = Math.pow(2, 32);
-  var h32 = (sign << 31) | ((exp+1023) << 20) |
-      (frac1 / b32) & 0x0fffff;
-  var l32 = frac1 % b32;
-  this.bufferBuilder.append(0xcb);
-  this.pack_int32(h32);
-  this.pack_int32(l32);
-}
-
-Packer.prototype.pack_object = function(obj){
-  var keys = Object.keys(obj);
-  var length = keys.length;
-  if (length <= 0x0f){
-    this.pack_uint8(0x80 + length);
-  } else if (length <= 0xffff){
-    this.bufferBuilder.append(0xde);
-    this.pack_uint16(length);
-  } else if (length <= 0xffffffff){
-    this.bufferBuilder.append(0xdf);
-    this.pack_uint32(length);
-  } else{
-    throw new Error('Invalid length');
-  }
-  for(var prop in obj){
-    if (obj.hasOwnProperty(prop)){
-      this.pack(prop);
-      this.pack(obj[prop]);
-    }
-  }
-}
-
-Packer.prototype.pack_uint8 = function(num){
-  this.bufferBuilder.append(num);
-}
-
-Packer.prototype.pack_uint16 = function(num){
-  this.bufferBuilder.append(num >> 8);
-  this.bufferBuilder.append(num & 0xff);
-}
-
-Packer.prototype.pack_uint32 = function(num){
-  var n = num & 0xffffffff;
-  this.bufferBuilder.append((n & 0xff000000) >>> 24);
-  this.bufferBuilder.append((n & 0x00ff0000) >>> 16);
-  this.bufferBuilder.append((n & 0x0000ff00) >>>  8);
-  this.bufferBuilder.append((n & 0x000000ff));
-}
-
-Packer.prototype.pack_uint64 = function(num){
-  var high = num / Math.pow(2, 32);
-  var low  = num % Math.pow(2, 32);
-  this.bufferBuilder.append((high & 0xff000000) >>> 24);
-  this.bufferBuilder.append((high & 0x00ff0000) >>> 16);
-  this.bufferBuilder.append((high & 0x0000ff00) >>>  8);
-  this.bufferBuilder.append((high & 0x000000ff));
-  this.bufferBuilder.append((low  & 0xff000000) >>> 24);
-  this.bufferBuilder.append((low  & 0x00ff0000) >>> 16);
-  this.bufferBuilder.append((low  & 0x0000ff00) >>>  8);
-  this.bufferBuilder.append((low  & 0x000000ff));
-}
-
-Packer.prototype.pack_int8 = function(num){
-  this.bufferBuilder.append(num & 0xff);
-}
-
-Packer.prototype.pack_int16 = function(num){
-  this.bufferBuilder.append((num & 0xff00) >> 8);
-  this.bufferBuilder.append(num & 0xff);
-}
-
-Packer.prototype.pack_int32 = function(num){
-  this.bufferBuilder.append((num >>> 24) & 0xff);
-  this.bufferBuilder.append((num & 0x00ff0000) >>> 16);
-  this.bufferBuilder.append((num & 0x0000ff00) >>> 8);
-  this.bufferBuilder.append((num & 0x000000ff));
-}
-
-Packer.prototype.pack_int64 = function(num){
-  var high = Math.floor(num / Math.pow(2, 32));
-  var low  = num % Math.pow(2, 32);
-  this.bufferBuilder.append((high & 0xff000000) >>> 24);
-  this.bufferBuilder.append((high & 0x00ff0000) >>> 16);
-  this.bufferBuilder.append((high & 0x0000ff00) >>>  8);
-  this.bufferBuilder.append((high & 0x000000ff));
-  this.bufferBuilder.append((low  & 0xff000000) >>> 24);
-  this.bufferBuilder.append((low  & 0x00ff0000) >>> 16);
-  this.bufferBuilder.append((low  & 0x0000ff00) >>>  8);
-  this.bufferBuilder.append((low  & 0x000000ff));
-}
-
-function _utf8Replace(m){
-  var code = m.charCodeAt(0);
-
-  if(code <= 0x7ff) return '00';
-  if(code <= 0xffff) return '000';
-  if(code <= 0x1fffff) return '0000';
-  if(code <= 0x3ffffff) return '00000';
-  return '000000';
-}
-
-function utf8Length(str){
-  if (str.length > 600) {
-    // Blob method faster for large strings
-    return (new Blob([str])).size;
-  } else {
-    return str.replace(/[^\u0000-\u007F]/g, _utf8Replace).length;
-  }
-}
-
-},{"./bufferbuilder":11}],11:[function(require,module,exports){
-var binaryFeatures = {};
-binaryFeatures.useBlobBuilder = (function(){
-  try {
-    new Blob([]);
-    return false;
-  } catch (e) {
-    return true;
-  }
-})();
-
-binaryFeatures.useArrayBufferView = !binaryFeatures.useBlobBuilder && (function(){
-  try {
-    return (new Blob([new Uint8Array([])])).size === 0;
-  } catch (e) {
-    return true;
-  }
-})();
-
-module.exports.binaryFeatures = binaryFeatures;
-var BlobBuilder = module.exports.BlobBuilder;
-if (typeof window != 'undefined') {
-  BlobBuilder = module.exports.BlobBuilder = window.WebKitBlobBuilder ||
-    window.MozBlobBuilder || window.MSBlobBuilder || window.BlobBuilder;
-}
-
-function BufferBuilder(){
-  this._pieces = [];
-  this._parts = [];
-}
-
-BufferBuilder.prototype.append = function(data) {
-  if(typeof data === 'number') {
-    this._pieces.push(data);
-  } else {
-    this.flush();
-    this._parts.push(data);
-  }
-};
-
-BufferBuilder.prototype.flush = function() {
-  if (this._pieces.length > 0) {
-    var buf = new Uint8Array(this._pieces);
-    if(!binaryFeatures.useArrayBufferView) {
-      buf = buf.buffer;
-    }
-    this._parts.push(buf);
-    this._pieces = [];
-  }
-};
-
-BufferBuilder.prototype.getBuffer = function() {
-  this.flush();
-  if(binaryFeatures.useBlobBuilder) {
-    var builder = new BlobBuilder();
-    for(var i = 0, ii = this._parts.length; i < ii; i++) {
-      builder.append(this._parts[i]);
-    }
-    return builder.getBlob();
-  } else {
-    return new Blob(this._parts);
-  }
-};
-
-module.exports.BufferBuilder = BufferBuilder;
-
-},{}],12:[function(require,module,exports){
-var util = require('./util');
-
-/**
- * Reliable transfer for Chrome Canary DataChannel impl.
- * Author: @michellebu
- */
-function Reliable(dc, debug) {
-  if (!(this instanceof Reliable)) return new Reliable(dc);
-  this._dc = dc;
-
-  util.debug = debug;
-
-  // Messages sent/received so far.
-  // id: { ack: n, chunks: [...] }
-  this._outgoing = {};
-  // id: { ack: ['ack', id, n], chunks: [...] }
-  this._incoming = {};
-  this._received = {};
-
-  // Window size.
-  this._window = 1000;
-  // MTU.
-  this._mtu = 500;
-  // Interval for setInterval. In ms.
-  this._interval = 0;
-
-  // Messages sent.
-  this._count = 0;
-
-  // Outgoing message queue.
-  this._queue = [];
-
-  this._setupDC();
-};
-
-// Send a message reliably.
-Reliable.prototype.send = function(msg) {
-  // Determine if chunking is necessary.
-  var bl = util.pack(msg);
-  if (bl.size < this._mtu) {
-    this._handleSend(['no', bl]);
-    return;
-  }
-
-  this._outgoing[this._count] = {
-    ack: 0,
-    chunks: this._chunk(bl)
-  };
-
-  if (util.debug) {
-    this._outgoing[this._count].timer = new Date();
-  }
-
-  // Send prelim window.
-  this._sendWindowedChunks(this._count);
-  this._count += 1;
-};
-
-// Set up interval for processing queue.
-Reliable.prototype._setupInterval = function() {
-  // TODO: fail gracefully.
-
-  var self = this;
-  this._timeout = setInterval(function() {
-    // FIXME: String stuff makes things terribly async.
-    var msg = self._queue.shift();
-    if (msg._multiple) {
-      for (var i = 0, ii = msg.length; i < ii; i += 1) {
-        self._intervalSend(msg[i]);
-      }
-    } else {
-      self._intervalSend(msg);
-    }
-  }, this._interval);
-};
-
-Reliable.prototype._intervalSend = function(msg) {
-  var self = this;
-  msg = util.pack(msg);
-  util.blobToBinaryString(msg, function(str) {
-    self._dc.send(str);
-  });
-  if (self._queue.length === 0) {
-    clearTimeout(self._timeout);
-    self._timeout = null;
-    //self._processAcks();
-  }
-};
-
-// Go through ACKs to send missing pieces.
-Reliable.prototype._processAcks = function() {
-  for (var id in this._outgoing) {
-    if (this._outgoing.hasOwnProperty(id)) {
-      this._sendWindowedChunks(id);
-    }
-  }
-};
-
-// Handle sending a message.
-// FIXME: Don't wait for interval time for all messages...
-Reliable.prototype._handleSend = function(msg) {
-  var push = true;
-  for (var i = 0, ii = this._queue.length; i < ii; i += 1) {
-    var item = this._queue[i];
-    if (item === msg) {
-      push = false;
-    } else if (item._multiple && item.indexOf(msg) !== -1) {
-      push = false;
-    }
-  }
-  if (push) {
-    this._queue.push(msg);
-    if (!this._timeout) {
-      this._setupInterval();
-    }
-  }
-};
-
-// Set up DataChannel handlers.
-Reliable.prototype._setupDC = function() {
-  // Handle various message types.
-  var self = this;
-  this._dc.onmessage = function(e) {
-    var msg = e.data;
-    var datatype = msg.constructor;
-    // FIXME: msg is String until binary is supported.
-    // Once that happens, this will have to be smarter.
-    if (datatype === String) {
-      var ab = util.binaryStringToArrayBuffer(msg);
-      msg = util.unpack(ab);
-      self._handleMessage(msg);
-    }
-  };
-};
-
-// Handles an incoming message.
-Reliable.prototype._handleMessage = function(msg) {
-  var id = msg[1];
-  var idata = this._incoming[id];
-  var odata = this._outgoing[id];
-  var data;
-  switch (msg[0]) {
-    // No chunking was done.
-    case 'no':
-      var message = id;
-      if (!!message) {
-        this.onmessage(util.unpack(message));
-      }
-      break;
-    // Reached the end of the message.
-    case 'end':
-      data = idata;
-
-      // In case end comes first.
-      this._received[id] = msg[2];
-
-      if (!data) {
-        break;
-      }
-
-      this._ack(id);
-      break;
-    case 'ack':
-      data = odata;
-      if (!!data) {
-        var ack = msg[2];
-        // Take the larger ACK, for out of order messages.
-        data.ack = Math.max(ack, data.ack);
-
-        // Clean up when all chunks are ACKed.
-        if (data.ack >= data.chunks.length) {
-          util.log('Time: ', new Date() - data.timer);
-          delete this._outgoing[id];
-        } else {
-          this._processAcks();
-        }
-      }
-      // If !data, just ignore.
-      break;
-    // Received a chunk of data.
-    case 'chunk':
-      // Create a new entry if none exists.
-      data = idata;
-      if (!data) {
-        var end = this._received[id];
-        if (end === true) {
-          break;
-        }
-        data = {
-          ack: ['ack', id, 0],
-          chunks: []
-        };
-        this._incoming[id] = data;
-      }
-
-      var n = msg[2];
-      var chunk = msg[3];
-      data.chunks[n] = new Uint8Array(chunk);
-
-      // If we get the chunk we're looking for, ACK for next missing.
-      // Otherwise, ACK the same N again.
-      if (n === data.ack[2]) {
-        this._calculateNextAck(id);
-      }
-      this._ack(id);
-      break;
-    default:
-      // Shouldn't happen, but would make sense for message to just go
-      // through as is.
-      this._handleSend(msg);
-      break;
-  }
-};
-
-// Chunks BL into smaller messages.
-Reliable.prototype._chunk = function(bl) {
-  var chunks = [];
-  var size = bl.size;
-  var start = 0;
-  while (start < size) {
-    var end = Math.min(size, start + this._mtu);
-    var b = bl.slice(start, end);
-    var chunk = {
-      payload: b
-    }
-    chunks.push(chunk);
-    start = end;
-  }
-  util.log('Created', chunks.length, 'chunks.');
-  return chunks;
-};
-
-// Sends ACK N, expecting Nth blob chunk for message ID.
-Reliable.prototype._ack = function(id) {
-  var ack = this._incoming[id].ack;
-
-  // if ack is the end value, then call _complete.
-  if (this._received[id] === ack[2]) {
-    this._complete(id);
-    this._received[id] = true;
-  }
-
-  this._handleSend(ack);
-};
-
-// Calculates the next ACK number, given chunks.
-Reliable.prototype._calculateNextAck = function(id) {
-  var data = this._incoming[id];
-  var chunks = data.chunks;
-  for (var i = 0, ii = chunks.length; i < ii; i += 1) {
-    // This chunk is missing!!! Better ACK for it.
-    if (chunks[i] === undefined) {
-      data.ack[2] = i;
-      return;
-    }
-  }
-  data.ack[2] = chunks.length;
-};
-
-// Sends the next window of chunks.
-Reliable.prototype._sendWindowedChunks = function(id) {
-  util.log('sendWindowedChunks for: ', id);
-  var data = this._outgoing[id];
-  var ch = data.chunks;
-  var chunks = [];
-  var limit = Math.min(data.ack + this._window, ch.length);
-  for (var i = data.ack; i < limit; i += 1) {
-    if (!ch[i].sent || i === data.ack) {
-      ch[i].sent = true;
-      chunks.push(['chunk', id, i, ch[i].payload]);
-    }
-  }
-  if (data.ack + this._window >= ch.length) {
-    chunks.push(['end', id, ch.length])
-  }
-  chunks._multiple = true;
-  this._handleSend(chunks);
-};
-
-// Puts together a message from chunks.
-Reliable.prototype._complete = function(id) {
-  util.log('Completed called for', id);
-  var self = this;
-  var chunks = this._incoming[id].chunks;
-  var bl = new Blob(chunks);
-  util.blobToArrayBuffer(bl, function(ab) {
-    self.onmessage(util.unpack(ab));
-  });
-  delete this._incoming[id];
-};
-
-// Ups bandwidth limit on SDP. Meant to be called during offer/answer.
-Reliable.higherBandwidthSDP = function(sdp) {
-  // AS stands for Application-Specific Maximum.
-  // Bandwidth number is in kilobits / sec.
-  // See RFC for more info: http://www.ietf.org/rfc/rfc2327.txt
-
-  // Chrome 31+ doesn't want us munging the SDP, so we'll let them have their
-  // way.
-  var version = navigator.appVersion.match(/Chrome\/(.*?) /);
-  if (version) {
-    version = parseInt(version[1].split('.').shift());
-    if (version < 31) {
-      var parts = sdp.split('b=AS:30');
-      var replace = 'b=AS:102400'; // 100 Mbps
-      if (parts.length > 1) {
-        return parts[0] + replace + parts[1];
-      }
-    }
-  }
-
-  return sdp;
-};
-
-// Overwritten, typically.
-Reliable.prototype.onmessage = function(msg) {};
-
-module.exports.Reliable = Reliable;
-
-},{"./util":13}],13:[function(require,module,exports){
-var BinaryPack = require('js-binarypack');
-
-var util = {
-  debug: false,
-  
-  inherits: function(ctor, superCtor) {
-    ctor.super_ = superCtor;
-    ctor.prototype = Object.create(superCtor.prototype, {
-      constructor: {
-        value: ctor,
-        enumerable: false,
-        writable: true,
-        configurable: true
-      }
-    });
-  },
-  extend: function(dest, source) {
-    for(var key in source) {
-      if(source.hasOwnProperty(key)) {
-        dest[key] = source[key];
-      }
-    }
-    return dest;
-  },
-  pack: BinaryPack.pack,
-  unpack: BinaryPack.unpack,
-  
-  log: function () {
-    if (util.debug) {
-      var copy = [];
-      for (var i = 0; i < arguments.length; i++) {
-        copy[i] = arguments[i];
-      }
-      copy.unshift('Reliable: ');
-      console.log.apply(console, copy);
-    }
-  },
-
-  setZeroTimeout: (function(global) {
-    var timeouts = [];
-    var messageName = 'zero-timeout-message';
-
-    // Like setTimeout, but only takes a function argument.	 There's
-    // no time argument (always zero) and no arguments (you have to
-    // use a closure).
-    function setZeroTimeoutPostMessage(fn) {
-      timeouts.push(fn);
-      global.postMessage(messageName, '*');
-    }		
-
-    function handleMessage(event) {
-      if (event.source == global && event.data == messageName) {
-        if (event.stopPropagation) {
-          event.stopPropagation();
-        }
-        if (timeouts.length) {
-          timeouts.shift()();
-        }
-      }
-    }
-    if (global.addEventListener) {
-      global.addEventListener('message', handleMessage, true);
-    } else if (global.attachEvent) {
-      global.attachEvent('onmessage', handleMessage);
-    }
-    return setZeroTimeoutPostMessage;
-  }(this)),
-  
-  blobToArrayBuffer: function(blob, cb){
-    var fr = new FileReader();
-    fr.onload = function(evt) {
-      cb(evt.target.result);
-    };
-    fr.readAsArrayBuffer(blob);
-  },
-  blobToBinaryString: function(blob, cb){
-    var fr = new FileReader();
-    fr.onload = function(evt) {
-      cb(evt.target.result);
-    };
-    fr.readAsBinaryString(blob);
-  },
-  binaryStringToArrayBuffer: function(binary) {
-    var byteArray = new Uint8Array(binary.length);
-    for (var i = 0; i < binary.length; i++) {
-      byteArray[i] = binary.charCodeAt(i) & 0xff;
-    }
-    return byteArray.buffer;
-  },
-  randomToken: function () {
-    return Math.random().toString(36).substr(2);
-  }
-};
-
-module.exports = util;
-
-},{"js-binarypack":10}],14:[function(require,module,exports){
-/*
- *  Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree.
- */
- /* eslint-env node */
-'use strict';
-
-var SDPUtils = require('sdp');
-
-function fixStatsType(stat) {
-  return {
-    inboundrtp: 'inbound-rtp',
-    outboundrtp: 'outbound-rtp',
-    candidatepair: 'candidate-pair',
-    localcandidate: 'local-candidate',
-    remotecandidate: 'remote-candidate'
-  }[stat.type] || stat.type;
-}
-
-function writeMediaSection(transceiver, caps, type, stream, dtlsRole) {
-  var sdp = SDPUtils.writeRtpDescription(transceiver.kind, caps);
-
-  // Map ICE parameters (ufrag, pwd) to SDP.
-  sdp += SDPUtils.writeIceParameters(
-      transceiver.iceGatherer.getLocalParameters());
-
-  // Map DTLS parameters to SDP.
-  sdp += SDPUtils.writeDtlsParameters(
-      transceiver.dtlsTransport.getLocalParameters(),
-      type === 'offer' ? 'actpass' : dtlsRole || 'active');
-
-  sdp += 'a=mid:' + transceiver.mid + '\r\n';
-
-  if (transceiver.rtpSender && transceiver.rtpReceiver) {
-    sdp += 'a=sendrecv\r\n';
-  } else if (transceiver.rtpSender) {
-    sdp += 'a=sendonly\r\n';
-  } else if (transceiver.rtpReceiver) {
-    sdp += 'a=recvonly\r\n';
-  } else {
-    sdp += 'a=inactive\r\n';
-  }
-
-  if (transceiver.rtpSender) {
-    var trackId = transceiver.rtpSender._initialTrackId ||
-        transceiver.rtpSender.track.id;
-    transceiver.rtpSender._initialTrackId = trackId;
-    // spec.
-    var msid = 'msid:' + (stream ? stream.id : '-') + ' ' +
-        trackId + '\r\n';
-    sdp += 'a=' + msid;
-    // for Chrome. Legacy should no longer be required.
-    sdp += 'a=ssrc:' + transceiver.sendEncodingParameters[0].ssrc +
-        ' ' + msid;
-
-    // RTX
-    if (transceiver.sendEncodingParameters[0].rtx) {
-      sdp += 'a=ssrc:' + transceiver.sendEncodingParameters[0].rtx.ssrc +
-          ' ' + msid;
-      sdp += 'a=ssrc-group:FID ' +
-          transceiver.sendEncodingParameters[0].ssrc + ' ' +
-          transceiver.sendEncodingParameters[0].rtx.ssrc +
-          '\r\n';
-    }
-  }
-  // FIXME: this should be written by writeRtpDescription.
-  sdp += 'a=ssrc:' + transceiver.sendEncodingParameters[0].ssrc +
-      ' cname:' + SDPUtils.localCName + '\r\n';
-  if (transceiver.rtpSender && transceiver.sendEncodingParameters[0].rtx) {
-    sdp += 'a=ssrc:' + transceiver.sendEncodingParameters[0].rtx.ssrc +
-        ' cname:' + SDPUtils.localCName + '\r\n';
-  }
-  return sdp;
-}
-
-// Edge does not like
-// 1) stun: filtered after 14393 unless ?transport=udp is present
-// 2) turn: that does not have all of turn:host:port?transport=udp
-// 3) turn: with ipv6 addresses
-// 4) turn: occurring muliple times
-function filterIceServers(iceServers, edgeVersion) {
-  var hasTurn = false;
-  iceServers = JSON.parse(JSON.stringify(iceServers));
-  return iceServers.filter(function(server) {
-    if (server && (server.urls || server.url)) {
-      var urls = server.urls || server.url;
-      if (server.url && !server.urls) {
-        console.warn('RTCIceServer.url is deprecated! Use urls instead.');
-      }
-      var isString = typeof urls === 'string';
-      if (isString) {
-        urls = [urls];
-      }
-      urls = urls.filter(function(url) {
-        var validTurn = url.indexOf('turn:') === 0 &&
-            url.indexOf('transport=udp') !== -1 &&
-            url.indexOf('turn:[') === -1 &&
-            !hasTurn;
-
-        if (validTurn) {
-          hasTurn = true;
-          return true;
-        }
-        return url.indexOf('stun:') === 0 && edgeVersion >= 14393 &&
-            url.indexOf('?transport=udp') === -1;
-      });
-
-      delete server.url;
-      server.urls = isString ? urls[0] : urls;
-      return !!urls.length;
-    }
-  });
-}
-
-// Determines the intersection of local and remote capabilities.
-function getCommonCapabilities(localCapabilities, remoteCapabilities) {
-  var commonCapabilities = {
-    codecs: [],
-    headerExtensions: [],
-    fecMechanisms: []
-  };
-
-  var findCodecByPayloadType = function(pt, codecs) {
-    pt = parseInt(pt, 10);
-    for (var i = 0; i < codecs.length; i++) {
-      if (codecs[i].payloadType === pt ||
-          codecs[i].preferredPayloadType === pt) {
-        return codecs[i];
-      }
-    }
-  };
-
-  var rtxCapabilityMatches = function(lRtx, rRtx, lCodecs, rCodecs) {
-    var lCodec = findCodecByPayloadType(lRtx.parameters.apt, lCodecs);
-    var rCodec = findCodecByPayloadType(rRtx.parameters.apt, rCodecs);
-    return lCodec && rCodec &&
-        lCodec.name.toLowerCase() === rCodec.name.toLowerCase();
-  };
-
-  localCapabilities.codecs.forEach(function(lCodec) {
-    for (var i = 0; i < remoteCapabilities.codecs.length; i++) {
-      var rCodec = remoteCapabilities.codecs[i];
-      if (lCodec.name.toLowerCase() === rCodec.name.toLowerCase() &&
-          lCodec.clockRate === rCodec.clockRate) {
-        if (lCodec.name.toLowerCase() === 'rtx' &&
-            lCodec.parameters && rCodec.parameters.apt) {
-          // for RTX we need to find the local rtx that has a apt
-          // which points to the same local codec as the remote one.
-          if (!rtxCapabilityMatches(lCodec, rCodec,
-              localCapabilities.codecs, remoteCapabilities.codecs)) {
-            continue;
-          }
-        }
-        rCodec = JSON.parse(JSON.stringify(rCodec)); // deepcopy
-        // number of channels is the highest common number of channels
-        rCodec.numChannels = Math.min(lCodec.numChannels,
-            rCodec.numChannels);
-        // push rCodec so we reply with offerer payload type
-        commonCapabilities.codecs.push(rCodec);
-
-        // determine common feedback mechanisms
-        rCodec.rtcpFeedback = rCodec.rtcpFeedback.filter(function(fb) {
-          for (var j = 0; j < lCodec.rtcpFeedback.length; j++) {
-            if (lCodec.rtcpFeedback[j].type === fb.type &&
-                lCodec.rtcpFeedback[j].parameter === fb.parameter) {
-              return true;
-            }
-          }
-          return false;
-        });
-        // FIXME: also need to determine .parameters
-        //  see https://github.com/openpeer/ortc/issues/569
-        break;
-      }
-    }
-  });
-
-  localCapabilities.headerExtensions.forEach(function(lHeaderExtension) {
-    for (var i = 0; i < remoteCapabilities.headerExtensions.length;
-         i++) {
-      var rHeaderExtension = remoteCapabilities.headerExtensions[i];
-      if (lHeaderExtension.uri === rHeaderExtension.uri) {
-        commonCapabilities.headerExtensions.push(rHeaderExtension);
-        break;
-      }
-    }
-  });
-
-  // FIXME: fecMechanisms
-  return commonCapabilities;
-}
-
-// is action=setLocalDescription with type allowed in signalingState
-function isActionAllowedInSignalingState(action, type, signalingState) {
-  return {
-    offer: {
-      setLocalDescription: ['stable', 'have-local-offer'],
-      setRemoteDescription: ['stable', 'have-remote-offer']
-    },
-    answer: {
-      setLocalDescription: ['have-remote-offer', 'have-local-pranswer'],
-      setRemoteDescription: ['have-local-offer', 'have-remote-pranswer']
-    }
-  }[type][action].indexOf(signalingState) !== -1;
-}
-
-function maybeAddCandidate(iceTransport, candidate) {
-  // Edge's internal representation adds some fields therefore
-  // not all fieldѕ are taken into account.
-  var alreadyAdded = iceTransport.getRemoteCandidates()
-      .find(function(remoteCandidate) {
-        return candidate.foundation === remoteCandidate.foundation &&
-            candidate.ip === remoteCandidate.ip &&
-            candidate.port === remoteCandidate.port &&
-            candidate.priority === remoteCandidate.priority &&
-            candidate.protocol === remoteCandidate.protocol &&
-            candidate.type === remoteCandidate.type;
-      });
-  if (!alreadyAdded) {
-    iceTransport.addRemoteCandidate(candidate);
-  }
-  return !alreadyAdded;
-}
-
-
-function makeError(name, description) {
-  var e = new Error(description);
-  e.name = name;
-  // legacy error codes from https://heycam.github.io/webidl/#idl-DOMException-error-names
-  e.code = {
-    NotSupportedError: 9,
-    InvalidStateError: 11,
-    InvalidAccessError: 15,
-    TypeError: undefined,
-    OperationError: undefined
-  }[name];
-  return e;
-}
-
-module.exports = function(window, edgeVersion) {
-  // https://w3c.github.io/mediacapture-main/#mediastream
-  // Helper function to add the track to the stream and
-  // dispatch the event ourselves.
-  function addTrackToStreamAndFireEvent(track, stream) {
-    stream.addTrack(track);
-    stream.dispatchEvent(new window.MediaStreamTrackEvent('addtrack',
-        {track: track}));
-  }
-
-  function removeTrackFromStreamAndFireEvent(track, stream) {
-    stream.removeTrack(track);
-    stream.dispatchEvent(new window.MediaStreamTrackEvent('removetrack',
-        {track: track}));
-  }
-
-  function fireAddTrack(pc, track, receiver, streams) {
-    var trackEvent = new Event('track');
-    trackEvent.track = track;
-    trackEvent.receiver = receiver;
-    trackEvent.transceiver = {receiver: receiver};
-    trackEvent.streams = streams;
-    window.setTimeout(function() {
-      pc._dispatchEvent('track', trackEvent);
-    });
-  }
-
-  var RTCPeerConnection = function(config) {
-    var pc = this;
-
-    var _eventTarget = document.createDocumentFragment();
-    ['addEventListener', 'removeEventListener', 'dispatchEvent']
-        .forEach(function(method) {
-          pc[method] = _eventTarget[method].bind(_eventTarget);
-        });
-
-    this.canTrickleIceCandidates = null;
-
-    this.needNegotiation = false;
-
-    this.localStreams = [];
-    this.remoteStreams = [];
-
-    this._localDescription = null;
-    this._remoteDescription = null;
-
-    this.signalingState = 'stable';
-    this.iceConnectionState = 'new';
-    this.connectionState = 'new';
-    this.iceGatheringState = 'new';
-
-    config = JSON.parse(JSON.stringify(config || {}));
-
-    this.usingBundle = config.bundlePolicy === 'max-bundle';
-    if (config.rtcpMuxPolicy === 'negotiate') {
-      throw(makeError('NotSupportedError',
-          'rtcpMuxPolicy \'negotiate\' is not supported'));
-    } else if (!config.rtcpMuxPolicy) {
-      config.rtcpMuxPolicy = 'require';
-    }
-
-    switch (config.iceTransportPolicy) {
-      case 'all':
-      case 'relay':
-        break;
-      default:
-        config.iceTransportPolicy = 'all';
-        break;
-    }
-
-    switch (config.bundlePolicy) {
-      case 'balanced':
-      case 'max-compat':
-      case 'max-bundle':
-        break;
-      default:
-        config.bundlePolicy = 'balanced';
-        break;
-    }
-
-    config.iceServers = filterIceServers(config.iceServers || [], edgeVersion);
-
-    this._iceGatherers = [];
-    if (config.iceCandidatePoolSize) {
-      for (var i = config.iceCandidatePoolSize; i > 0; i--) {
-        this._iceGatherers.push(new window.RTCIceGatherer({
-          iceServers: config.iceServers,
-          gatherPolicy: config.iceTransportPolicy
-        }));
-      }
-    } else {
-      config.iceCandidatePoolSize = 0;
-    }
-
-    this._config = config;
-
-    // per-track iceGathers, iceTransports, dtlsTransports, rtpSenders, ...
-    // everything that is needed to describe a SDP m-line.
-    this.transceivers = [];
-
-    this._sdpSessionId = SDPUtils.generateSessionId();
-    this._sdpSessionVersion = 0;
-
-    this._dtlsRole = undefined; // role for a=setup to use in answers.
-
-    this._isClosed = false;
-  };
-
-  Object.defineProperty(RTCPeerConnection.prototype, 'localDescription', {
-    configurable: true,
-    get: function() {
-      return this._localDescription;
-    }
-  });
-  Object.defineProperty(RTCPeerConnection.prototype, 'remoteDescription', {
-    configurable: true,
-    get: function() {
-      return this._remoteDescription;
-    }
-  });
-
-  // set up event handlers on prototype
-  RTCPeerConnection.prototype.onicecandidate = null;
-  RTCPeerConnection.prototype.onaddstream = null;
-  RTCPeerConnection.prototype.ontrack = null;
-  RTCPeerConnection.prototype.onremovestream = null;
-  RTCPeerConnection.prototype.onsignalingstatechange = null;
-  RTCPeerConnection.prototype.oniceconnectionstatechange = null;
-  RTCPeerConnection.prototype.onconnectionstatechange = null;
-  RTCPeerConnection.prototype.onicegatheringstatechange = null;
-  RTCPeerConnection.prototype.onnegotiationneeded = null;
-  RTCPeerConnection.prototype.ondatachannel = null;
-
-  RTCPeerConnection.prototype._dispatchEvent = function(name, event) {
-    if (this._isClosed) {
-      return;
-    }
-    this.dispatchEvent(event);
-    if (typeof this['on' + name] === 'function') {
-      this['on' + name](event);
-    }
-  };
-
-  RTCPeerConnection.prototype._emitGatheringStateChange = function() {
-    var event = new Event('icegatheringstatechange');
-    this._dispatchEvent('icegatheringstatechange', event);
-  };
-
-  RTCPeerConnection.prototype.getConfiguration = function() {
-    return this._config;
-  };
-
-  RTCPeerConnection.prototype.getLocalStreams = function() {
-    return this.localStreams;
-  };
-
-  RTCPeerConnection.prototype.getRemoteStreams = function() {
-    return this.remoteStreams;
-  };
-
-  // internal helper to create a transceiver object.
-  // (which is not yet the same as the WebRTC 1.0 transceiver)
-  RTCPeerConnection.prototype._createTransceiver = function(kind, doNotAdd) {
-    var hasBundleTransport = this.transceivers.length > 0;
-    var transceiver = {
-      track: null,
-      iceGatherer: null,
-      iceTransport: null,
-      dtlsTransport: null,
-      localCapabilities: null,
-      remoteCapabilities: null,
-      rtpSender: null,
-      rtpReceiver: null,
-      kind: kind,
-      mid: null,
-      sendEncodingParameters: null,
-      recvEncodingParameters: null,
-      stream: null,
-      associatedRemoteMediaStreams: [],
-      wantReceive: true
-    };
-    if (this.usingBundle && hasBundleTransport) {
-      transceiver.iceTransport = this.transceivers[0].iceTransport;
-      transceiver.dtlsTransport = this.transceivers[0].dtlsTransport;
-    } else {
-      var transports = this._createIceAndDtlsTransports();
-      transceiver.iceTransport = transports.iceTransport;
-      transceiver.dtlsTransport = transports.dtlsTransport;
-    }
-    if (!doNotAdd) {
-      this.transceivers.push(transceiver);
-    }
-    return transceiver;
-  };
-
-  RTCPeerConnection.prototype.addTrack = function(track, stream) {
-    if (this._isClosed) {
-      throw makeError('InvalidStateError',
-          'Attempted to call addTrack on a closed peerconnection.');
-    }
-
-    var alreadyExists = this.transceivers.find(function(s) {
-      return s.track === track;
-    });
-
-    if (alreadyExists) {
-      throw makeError('InvalidAccessError', 'Track already exists.');
-    }
-
-    var transceiver;
-    for (var i = 0; i < this.transceivers.length; i++) {
-      if (!this.transceivers[i].track &&
-          this.transceivers[i].kind === track.kind) {
-        transceiver = this.transceivers[i];
-      }
-    }
-    if (!transceiver) {
-      transceiver = this._createTransceiver(track.kind);
-    }
-
-    this._maybeFireNegotiationNeeded();
-
-    if (this.localStreams.indexOf(stream) === -1) {
-      this.localStreams.push(stream);
-    }
-
-    transceiver.track = track;
-    transceiver.stream = stream;
-    transceiver.rtpSender = new window.RTCRtpSender(track,
-        transceiver.dtlsTransport);
-    return transceiver.rtpSender;
-  };
-
-  RTCPeerConnection.prototype.addStream = function(stream) {
-    var pc = this;
-    if (edgeVersion >= 15025) {
-      stream.getTracks().forEach(function(track) {
-        pc.addTrack(track, stream);
-      });
-    } else {
-      // Clone is necessary for local demos mostly, attaching directly
-      // to two different senders does not work (build 10547).
-      // Fixed in 15025 (or earlier)
-      var clonedStream = stream.clone();
-      stream.getTracks().forEach(function(track, idx) {
-        var clonedTrack = clonedStream.getTracks()[idx];
-        track.addEventListener('enabled', function(event) {
-          clonedTrack.enabled = event.enabled;
-        });
-      });
-      clonedStream.getTracks().forEach(function(track) {
-        pc.addTrack(track, clonedStream);
-      });
-    }
-  };
-
-  RTCPeerConnection.prototype.removeTrack = function(sender) {
-    if (this._isClosed) {
-      throw makeError('InvalidStateError',
-          'Attempted to call removeTrack on a closed peerconnection.');
-    }
-
-    if (!(sender instanceof window.RTCRtpSender)) {
-      throw new TypeError('Argument 1 of RTCPeerConnection.removeTrack ' +
-          'does not implement interface RTCRtpSender.');
-    }
-
-    var transceiver = this.transceivers.find(function(t) {
-      return t.rtpSender === sender;
-    });
-
-    if (!transceiver) {
-      throw makeError('InvalidAccessError',
-          'Sender was not created by this connection.');
-    }
-    var stream = transceiver.stream;
-
-    transceiver.rtpSender.stop();
-    transceiver.rtpSender = null;
-    transceiver.track = null;
-    transceiver.stream = null;
-
-    // remove the stream from the set of local streams
-    var localStreams = this.transceivers.map(function(t) {
-      return t.stream;
-    });
-    if (localStreams.indexOf(stream) === -1 &&
-        this.localStreams.indexOf(stream) > -1) {
-      this.localStreams.splice(this.localStreams.indexOf(stream), 1);
-    }
-
-    this._maybeFireNegotiationNeeded();
-  };
-
-  RTCPeerConnection.prototype.removeStream = function(stream) {
-    var pc = this;
-    stream.getTracks().forEach(function(track) {
-      var sender = pc.getSenders().find(function(s) {
-        return s.track === track;
-      });
-      if (sender) {
-        pc.removeTrack(sender);
-      }
-    });
-  };
-
-  RTCPeerConnection.prototype.getSenders = function() {
-    return this.transceivers.filter(function(transceiver) {
-      return !!transceiver.rtpSender;
-    })
-    .map(function(transceiver) {
-      return transceiver.rtpSender;
-    });
-  };
-
-  RTCPeerConnection.prototype.getReceivers = function() {
-    return this.transceivers.filter(function(transceiver) {
-      return !!transceiver.rtpReceiver;
-    })
-    .map(function(transceiver) {
-      return transceiver.rtpReceiver;
-    });
-  };
-
-
-  RTCPeerConnection.prototype._createIceGatherer = function(sdpMLineIndex,
-      usingBundle) {
-    var pc = this;
-    if (usingBundle && sdpMLineIndex > 0) {
-      return this.transceivers[0].iceGatherer;
-    } else if (this._iceGatherers.length) {
-      return this._iceGatherers.shift();
-    }
-    var iceGatherer = new window.RTCIceGatherer({
-      iceServers: this._config.iceServers,
-      gatherPolicy: this._config.iceTransportPolicy
-    });
-    Object.defineProperty(iceGatherer, 'state',
-        {value: 'new', writable: true}
-    );
-
-    this.transceivers[sdpMLineIndex].bufferedCandidateEvents = [];
-    this.transceivers[sdpMLineIndex].bufferCandidates = function(event) {
-      var end = !event.candidate || Object.keys(event.candidate).length === 0;
-      // polyfill since RTCIceGatherer.state is not implemented in
-      // Edge 10547 yet.
-      iceGatherer.state = end ? 'completed' : 'gathering';
-      if (pc.transceivers[sdpMLineIndex].bufferedCandidateEvents !== null) {
-        pc.transceivers[sdpMLineIndex].bufferedCandidateEvents.push(event);
-      }
-    };
-    iceGatherer.addEventListener('localcandidate',
-      this.transceivers[sdpMLineIndex].bufferCandidates);
-    return iceGatherer;
-  };
-
-  // start gathering from an RTCIceGatherer.
-  RTCPeerConnection.prototype._gather = function(mid, sdpMLineIndex) {
-    var pc = this;
-    var iceGatherer = this.transceivers[sdpMLineIndex].iceGatherer;
-    if (iceGatherer.onlocalcandidate) {
-      return;
-    }
-    var bufferedCandidateEvents =
-      this.transceivers[sdpMLineIndex].bufferedCandidateEvents;
-    this.transceivers[sdpMLineIndex].bufferedCandidateEvents = null;
-    iceGatherer.removeEventListener('localcandidate',
-      this.transceivers[sdpMLineIndex].bufferCandidates);
-    iceGatherer.onlocalcandidate = function(evt) {
-      if (pc.usingBundle && sdpMLineIndex > 0) {
-        // if we know that we use bundle we can drop candidates with
-        // ѕdpMLineIndex > 0. If we don't do this then our state gets
-        // confused since we dispose the extra ice gatherer.
-        return;
-      }
-      var event = new Event('icecandidate');
-      event.candidate = {sdpMid: mid, sdpMLineIndex: sdpMLineIndex};
-
-      var cand = evt.candidate;
-      // Edge emits an empty object for RTCIceCandidateComplete‥
-      var end = !cand || Object.keys(cand).length === 0;
-      if (end) {
-        // polyfill since RTCIceGatherer.state is not implemented in
-        // Edge 10547 yet.
-        if (iceGatherer.state === 'new' || iceGatherer.state === 'gathering') {
-          iceGatherer.state = 'completed';
-        }
-      } else {
-        if (iceGatherer.state === 'new') {
-          iceGatherer.state = 'gathering';
-        }
-        // RTCIceCandidate doesn't have a component, needs to be added
-        cand.component = 1;
-        // also the usernameFragment. TODO: update SDP to take both variants.
-        cand.ufrag = iceGatherer.getLocalParameters().usernameFragment;
-
-        var serializedCandidate = SDPUtils.writeCandidate(cand);
-        event.candidate = Object.assign(event.candidate,
-            SDPUtils.parseCandidate(serializedCandidate));
-
-        event.candidate.candidate = serializedCandidate;
-        event.candidate.toJSON = function() {
-          return {
-            candidate: event.candidate.candidate,
-            sdpMid: event.candidate.sdpMid,
-            sdpMLineIndex: event.candidate.sdpMLineIndex,
-            usernameFragment: event.candidate.usernameFragment
-          };
-        };
-      }
-
-      // update local description.
-      var sections = SDPUtils.getMediaSections(pc._localDescription.sdp);
-      if (!end) {
-        sections[event.candidate.sdpMLineIndex] +=
-            'a=' + event.candidate.candidate + '\r\n';
-      } else {
-        sections[event.candidate.sdpMLineIndex] +=
-            'a=end-of-candidates\r\n';
-      }
-      pc._localDescription.sdp =
-          SDPUtils.getDescription(pc._localDescription.sdp) +
-          sections.join('');
-      var complete = pc.transceivers.every(function(transceiver) {
-        return transceiver.iceGatherer &&
-            transceiver.iceGatherer.state === 'completed';
-      });
-
-      if (pc.iceGatheringState !== 'gathering') {
-        pc.iceGatheringState = 'gathering';
-        pc._emitGatheringStateChange();
-      }
-
-      // Emit candidate. Also emit null candidate when all gatherers are
-      // complete.
-      if (!end) {
-        pc._dispatchEvent('icecandidate', event);
-      }
-      if (complete) {
-        pc._dispatchEvent('icecandidate', new Event('icecandidate'));
-        pc.iceGatheringState = 'complete';
-        pc._emitGatheringStateChange();
-      }
-    };
-
-    // emit already gathered candidates.
-    window.setTimeout(function() {
-      bufferedCandidateEvents.forEach(function(e) {
-        iceGatherer.onlocalcandidate(e);
-      });
-    }, 0);
-  };
-
-  // Create ICE transport and DTLS transport.
-  RTCPeerConnection.prototype._createIceAndDtlsTransports = function() {
-    var pc = this;
-    var iceTransport = new window.RTCIceTransport(null);
-    iceTransport.onicestatechange = function() {
-      pc._updateIceConnectionState();
-      pc._updateConnectionState();
-    };
-
-    var dtlsTransport = new window.RTCDtlsTransport(iceTransport);
-    dtlsTransport.ondtlsstatechange = function() {
-      pc._updateConnectionState();
-    };
-    dtlsTransport.onerror = function() {
-      // onerror does not set state to failed by itself.
-      Object.defineProperty(dtlsTransport, 'state',
-          {value: 'failed', writable: true});
-      pc._updateConnectionState();
-    };
-
-    return {
-      iceTransport: iceTransport,
-      dtlsTransport: dtlsTransport
-    };
-  };
-
-  // Destroy ICE gatherer, ICE transport and DTLS transport.
-  // Without triggering the callbacks.
-  RTCPeerConnection.prototype._disposeIceAndDtlsTransports = function(
-      sdpMLineIndex) {
-    var iceGatherer = this.transceivers[sdpMLineIndex].iceGatherer;
-    if (iceGatherer) {
-      delete iceGatherer.onlocalcandidate;
-      delete this.transceivers[sdpMLineIndex].iceGatherer;
-    }
-    var iceTransport = this.transceivers[sdpMLineIndex].iceTransport;
-    if (iceTransport) {
-      delete iceTransport.onicestatechange;
-      delete this.transceivers[sdpMLineIndex].iceTransport;
-    }
-    var dtlsTransport = this.transceivers[sdpMLineIndex].dtlsTransport;
-    if (dtlsTransport) {
-      delete dtlsTransport.ondtlsstatechange;
-      delete dtlsTransport.onerror;
-      delete this.transceivers[sdpMLineIndex].dtlsTransport;
-    }
-  };
-
-  // Start the RTP Sender and Receiver for a transceiver.
-  RTCPeerConnection.prototype._transceive = function(transceiver,
-      send, recv) {
-    var params = getCommonCapabilities(transceiver.localCapabilities,
-        transceiver.remoteCapabilities);
-    if (send && transceiver.rtpSender) {
-      params.encodings = transceiver.sendEncodingParameters;
-      params.rtcp = {
-        cname: SDPUtils.localCName,
-        compound: transceiver.rtcpParameters.compound
-      };
-      if (transceiver.recvEncodingParameters.length) {
-        params.rtcp.ssrc = transceiver.recvEncodingParameters[0].ssrc;
-      }
-      transceiver.rtpSender.send(params);
-    }
-    if (recv && transceiver.rtpReceiver && params.codecs.length > 0) {
-      // remove RTX field in Edge 14942
-      if (transceiver.kind === 'video'
-          && transceiver.recvEncodingParameters
-          && edgeVersion < 15019) {
-        transceiver.recvEncodingParameters.forEach(function(p) {
-          delete p.rtx;
-        });
-      }
-      if (transceiver.recvEncodingParameters.length) {
-        params.encodings = transceiver.recvEncodingParameters;
-      } else {
-        params.encodings = [{}];
-      }
-      params.rtcp = {
-        compound: transceiver.rtcpParameters.compound
-      };
-      if (transceiver.rtcpParameters.cname) {
-        params.rtcp.cname = transceiver.rtcpParameters.cname;
-      }
-      if (transceiver.sendEncodingParameters.length) {
-        params.rtcp.ssrc = transceiver.sendEncodingParameters[0].ssrc;
-      }
-      transceiver.rtpReceiver.receive(params);
-    }
-  };
-
-  RTCPeerConnection.prototype.setLocalDescription = function(description) {
-    var pc = this;
-
-    // Note: pranswer is not supported.
-    if (['offer', 'answer'].indexOf(description.type) === -1) {
-      return Promise.reject(makeError('TypeError',
-          'Unsupported type "' + description.type + '"'));
-    }
-
-    if (!isActionAllowedInSignalingState('setLocalDescription',
-        description.type, pc.signalingState) || pc._isClosed) {
-      return Promise.reject(makeError('InvalidStateError',
-          'Can not set local ' + description.type +
-          ' in state ' + pc.signalingState));
-    }
-
-    var sections;
-    var sessionpart;
-    if (description.type === 'offer') {
-      // VERY limited support for SDP munging. Limited to:
-      // * changing the order of codecs
-      sections = SDPUtils.splitSections(description.sdp);
-      sessionpart = sections.shift();
-      sections.forEach(function(mediaSection, sdpMLineIndex) {
-        var caps = SDPUtils.parseRtpParameters(mediaSection);
-        pc.transceivers[sdpMLineIndex].localCapabilities = caps;
-      });
-
-      pc.transceivers.forEach(function(transceiver, sdpMLineIndex) {
-        pc._gather(transceiver.mid, sdpMLineIndex);
-      });
-    } else if (description.type === 'answer') {
-      sections = SDPUtils.splitSections(pc._remoteDescription.sdp);
-      sessionpart = sections.shift();
-      var isIceLite = SDPUtils.matchPrefix(sessionpart,
-          'a=ice-lite').length > 0;
-      sections.forEach(function(mediaSection, sdpMLineIndex) {
-        var transceiver = pc.transceivers[sdpMLineIndex];
-        var iceGatherer = transceiver.iceGatherer;
-        var iceTransport = transceiver.iceTransport;
-        var dtlsTransport = transceiver.dtlsTransport;
-        var localCapabilities = transceiver.localCapabilities;
-        var remoteCapabilities = transceiver.remoteCapabilities;
-
-        // treat bundle-only as not-rejected.
-        var rejected = SDPUtils.isRejected(mediaSection) &&
-            SDPUtils.matchPrefix(mediaSection, 'a=bundle-only').length === 0;
-
-        if (!rejected && !transceiver.rejected) {
-          var remoteIceParameters = SDPUtils.getIceParameters(
-              mediaSection, sessionpart);
-          var remoteDtlsParameters = SDPUtils.getDtlsParameters(
-              mediaSection, sessionpart);
-          if (isIceLite) {
-            remoteDtlsParameters.role = 'server';
-          }
-
-          if (!pc.usingBundle || sdpMLineIndex === 0) {
-            pc._gather(transceiver.mid, sdpMLineIndex);
-            if (iceTransport.state === 'new') {
-              iceTransport.start(iceGatherer, remoteIceParameters,
-                  isIceLite ? 'controlling' : 'controlled');
-            }
-            if (dtlsTransport.state === 'new') {
-              dtlsTransport.start(remoteDtlsParameters);
-            }
-          }
-
-          // Calculate intersection of capabilities.
-          var params = getCommonCapabilities(localCapabilities,
-              remoteCapabilities);
-
-          // Start the RTCRtpSender. The RTCRtpReceiver for this
-          // transceiver has already been started in setRemoteDescription.
-          pc._transceive(transceiver,
-              params.codecs.length > 0,
-              false);
-        }
-      });
-    }
-
-    pc._localDescription = {
-      type: description.type,
-      sdp: description.sdp
-    };
-    if (description.type === 'offer') {
-      pc._updateSignalingState('have-local-offer');
-    } else {
-      pc._updateSignalingState('stable');
-    }
-
-    return Promise.resolve();
-  };
-
-  RTCPeerConnection.prototype.setRemoteDescription = function(description) {
-    var pc = this;
-
-    // Note: pranswer is not supported.
-    if (['offer', 'answer'].indexOf(description.type) === -1) {
-      return Promise.reject(makeError('TypeError',
-          'Unsupported type "' + description.type + '"'));
-    }
-
-    if (!isActionAllowedInSignalingState('setRemoteDescription',
-        description.type, pc.signalingState) || pc._isClosed) {
-      return Promise.reject(makeError('InvalidStateError',
-          'Can not set remote ' + description.type +
-          ' in state ' + pc.signalingState));
-    }
-
-    var streams = {};
-    pc.remoteStreams.forEach(function(stream) {
-      streams[stream.id] = stream;
-    });
-    var receiverList = [];
-    var sections = SDPUtils.splitSections(description.sdp);
-    var sessionpart = sections.shift();
-    var isIceLite = SDPUtils.matchPrefix(sessionpart,
-        'a=ice-lite').length > 0;
-    var usingBundle = SDPUtils.matchPrefix(sessionpart,
-        'a=group:BUNDLE ').length > 0;
-    pc.usingBundle = usingBundle;
-    var iceOptions = SDPUtils.matchPrefix(sessionpart,
-        'a=ice-options:')[0];
-    if (iceOptions) {
-      pc.canTrickleIceCandidates = iceOptions.substr(14).split(' ')
-          .indexOf('trickle') >= 0;
-    } else {
-      pc.canTrickleIceCandidates = false;
-    }
-
-    sections.forEach(function(mediaSection, sdpMLineIndex) {
-      var lines = SDPUtils.splitLines(mediaSection);
-      var kind = SDPUtils.getKind(mediaSection);
-      // treat bundle-only as not-rejected.
-      var rejected = SDPUtils.isRejected(mediaSection) &&
-          SDPUtils.matchPrefix(mediaSection, 'a=bundle-only').length === 0;
-      var protocol = lines[0].substr(2).split(' ')[2];
-
-      var direction = SDPUtils.getDirection(mediaSection, sessionpart);
-      var remoteMsid = SDPUtils.parseMsid(mediaSection);
-
-      var mid = SDPUtils.getMid(mediaSection) || SDPUtils.generateIdentifier();
-
-      // Reject datachannels which are not implemented yet.
-      if (rejected || (kind === 'application' && (protocol === 'DTLS/SCTP' ||
-          protocol === 'UDP/DTLS/SCTP'))) {
-        // TODO: this is dangerous in the case where a non-rejected m-line
-        //     becomes rejected.
-        pc.transceivers[sdpMLineIndex] = {
-          mid: mid,
-          kind: kind,
-          protocol: protocol,
-          rejected: true
-        };
-        return;
-      }
-
-      if (!rejected && pc.transceivers[sdpMLineIndex] &&
-          pc.transceivers[sdpMLineIndex].rejected) {
-        // recycle a rejected transceiver.
-        pc.transceivers[sdpMLineIndex] = pc._createTransceiver(kind, true);
-      }
-
-      var transceiver;
-      var iceGatherer;
-      var iceTransport;
-      var dtlsTransport;
-      var rtpReceiver;
-      var sendEncodingParameters;
-      var recvEncodingParameters;
-      var localCapabilities;
-
-      var track;
-      // FIXME: ensure the mediaSection has rtcp-mux set.
-      var remoteCapabilities = SDPUtils.parseRtpParameters(mediaSection);
-      var remoteIceParameters;
-      var remoteDtlsParameters;
-      if (!rejected) {
-        remoteIceParameters = SDPUtils.getIceParameters(mediaSection,
-            sessionpart);
-        remoteDtlsParameters = SDPUtils.getDtlsParameters(mediaSection,
-            sessionpart);
-        remoteDtlsParameters.role = 'client';
-      }
-      recvEncodingParameters =
-          SDPUtils.parseRtpEncodingParameters(mediaSection);
-
-      var rtcpParameters = SDPUtils.parseRtcpParameters(mediaSection);
-
-      var isComplete = SDPUtils.matchPrefix(mediaSection,
-          'a=end-of-candidates', sessionpart).length > 0;
-      var cands = SDPUtils.matchPrefix(mediaSection, 'a=candidate:')
-          .map(function(cand) {
-            return SDPUtils.parseCandidate(cand);
-          })
-          .filter(function(cand) {
-            return cand.component === 1;
-          });
-
-      // Check if we can use BUNDLE and dispose transports.
-      if ((description.type === 'offer' || description.type === 'answer') &&
-          !rejected && usingBundle && sdpMLineIndex > 0 &&
-          pc.transceivers[sdpMLineIndex]) {
-        pc._disposeIceAndDtlsTransports(sdpMLineIndex);
-        pc.transceivers[sdpMLineIndex].iceGatherer =
-            pc.transceivers[0].iceGatherer;
-        pc.transceivers[sdpMLineIndex].iceTransport =
-            pc.transceivers[0].iceTransport;
-        pc.transceivers[sdpMLineIndex].dtlsTransport =
-            pc.transceivers[0].dtlsTransport;
-        if (pc.transceivers[sdpMLineIndex].rtpSender) {
-          pc.transceivers[sdpMLineIndex].rtpSender.setTransport(
-              pc.transceivers[0].dtlsTransport);
-        }
-        if (pc.transceivers[sdpMLineIndex].rtpReceiver) {
-          pc.transceivers[sdpMLineIndex].rtpReceiver.setTransport(
-              pc.transceivers[0].dtlsTransport);
-        }
-      }
-      if (description.type === 'offer' && !rejected) {
-        transceiver = pc.transceivers[sdpMLineIndex] ||
-            pc._createTransceiver(kind);
-        transceiver.mid = mid;
-
-        if (!transceiver.iceGatherer) {
-          transceiver.iceGatherer = pc._createIceGatherer(sdpMLineIndex,
-              usingBundle);
-        }
-
-        if (cands.length && transceiver.iceTransport.state === 'new') {
-          if (isComplete && (!usingBundle || sdpMLineIndex === 0)) {
-            transceiver.iceTransport.setRemoteCandidates(cands);
-          } else {
-            cands.forEach(function(candidate) {
-              maybeAddCandidate(transceiver.iceTransport, candidate);
-            });
-          }
-        }
-
-        localCapabilities = window.RTCRtpReceiver.getCapabilities(kind);
-
-        // filter RTX until additional stuff needed for RTX is implemented
-        // in adapter.js
-        if (edgeVersion < 15019) {
-          localCapabilities.codecs = localCapabilities.codecs.filter(
-              function(codec) {
-                return codec.name !== 'rtx';
-              });
-        }
-
-        sendEncodingParameters = transceiver.sendEncodingParameters || [{
-          ssrc: (2 * sdpMLineIndex + 2) * 1001
-        }];
-
-        // TODO: rewrite to use http://w3c.github.io/webrtc-pc/#set-associated-remote-streams
-        var isNewTrack = false;
-        if (direction === 'sendrecv' || direction === 'sendonly') {
-          isNewTrack = !transceiver.rtpReceiver;
-          rtpReceiver = transceiver.rtpReceiver ||
-              new window.RTCRtpReceiver(transceiver.dtlsTransport, kind);
-
-          if (isNewTrack) {
-            var stream;
-            track = rtpReceiver.track;
-            // FIXME: does not work with Plan B.
-            if (remoteMsid && remoteMsid.stream === '-') {
-              // no-op. a stream id of '-' means: no associated stream.
-            } else if (remoteMsid) {
-              if (!streams[remoteMsid.stream]) {
-                streams[remoteMsid.stream] = new window.MediaStream();
-                Object.defineProperty(streams[remoteMsid.stream], 'id', {
-                  get: function() {
-                    return remoteMsid.stream;
-                  }
-                });
-              }
-              Object.defineProperty(track, 'id', {
-                get: function() {
-                  return remoteMsid.track;
-                }
-              });
-              stream = streams[remoteMsid.stream];
-            } else {
-              if (!streams.default) {
-                streams.default = new window.MediaStream();
-              }
-              stream = streams.default;
-            }
-            if (stream) {
-              addTrackToStreamAndFireEvent(track, stream);
-              transceiver.associatedRemoteMediaStreams.push(stream);
-            }
-            receiverList.push([track, rtpReceiver, stream]);
-          }
-        } else if (transceiver.rtpReceiver && transceiver.rtpReceiver.track) {
-          transceiver.associatedRemoteMediaStreams.forEach(function(s) {
-            var nativeTrack = s.getTracks().find(function(t) {
-              return t.id === transceiver.rtpReceiver.track.id;
-            });
-            if (nativeTrack) {
-              removeTrackFromStreamAndFireEvent(nativeTrack, s);
-            }
-          });
-          transceiver.associatedRemoteMediaStreams = [];
-        }
-
-        transceiver.localCapabilities = localCapabilities;
-        transceiver.remoteCapabilities = remoteCapabilities;
-        transceiver.rtpReceiver = rtpReceiver;
-        transceiver.rtcpParameters = rtcpParameters;
-        transceiver.sendEncodingParameters = sendEncodingParameters;
-        transceiver.recvEncodingParameters = recvEncodingParameters;
-
-        // Start the RTCRtpReceiver now. The RTPSender is started in
-        // setLocalDescription.
-        pc._transceive(pc.transceivers[sdpMLineIndex],
-            false,
-            isNewTrack);
-      } else if (description.type === 'answer' && !rejected) {
-        transceiver = pc.transceivers[sdpMLineIndex];
-        iceGatherer = transceiver.iceGatherer;
-        iceTransport = transceiver.iceTransport;
-        dtlsTransport = transceiver.dtlsTransport;
-        rtpReceiver = transceiver.rtpReceiver;
-        sendEncodingParameters = transceiver.sendEncodingParameters;
-        localCapabilities = transceiver.localCapabilities;
-
-        pc.transceivers[sdpMLineIndex].recvEncodingParameters =
-            recvEncodingParameters;
-        pc.transceivers[sdpMLineIndex].remoteCapabilities =
-            remoteCapabilities;
-        pc.transceivers[sdpMLineIndex].rtcpParameters = rtcpParameters;
-
-        if (cands.length && iceTransport.state === 'new') {
-          if ((isIceLite || isComplete) &&
-              (!usingBundle || sdpMLineIndex === 0)) {
-            iceTransport.setRemoteCandidates(cands);
-          } else {
-            cands.forEach(function(candidate) {
-              maybeAddCandidate(transceiver.iceTransport, candidate);
-            });
-          }
-        }
-
-        if (!usingBundle || sdpMLineIndex === 0) {
-          if (iceTransport.state === 'new') {
-            iceTransport.start(iceGatherer, remoteIceParameters,
-                'controlling');
-          }
-          if (dtlsTransport.state === 'new') {
-            dtlsTransport.start(remoteDtlsParameters);
-          }
-        }
-
-        pc._transceive(transceiver,
-            direction === 'sendrecv' || direction === 'recvonly',
-            direction === 'sendrecv' || direction === 'sendonly');
-
-        // TODO: rewrite to use http://w3c.github.io/webrtc-pc/#set-associated-remote-streams
-        if (rtpReceiver &&
-            (direction === 'sendrecv' || direction === 'sendonly')) {
-          track = rtpReceiver.track;
-          if (remoteMsid) {
-            if (!streams[remoteMsid.stream]) {
-              streams[remoteMsid.stream] = new window.MediaStream();
-            }
-            addTrackToStreamAndFireEvent(track, streams[remoteMsid.stream]);
-            receiverList.push([track, rtpReceiver, streams[remoteMsid.stream]]);
-          } else {
-            if (!streams.default) {
-              streams.default = new window.MediaStream();
-            }
-            addTrackToStreamAndFireEvent(track, streams.default);
-            receiverList.push([track, rtpReceiver, streams.default]);
-          }
-        } else {
-          // FIXME: actually the receiver should be created later.
-          delete transceiver.rtpReceiver;
-        }
-      }
-    });
-
-    if (pc._dtlsRole === undefined) {
-      pc._dtlsRole = description.type === 'offer' ? 'active' : 'passive';
-    }
-
-    pc._remoteDescription = {
-      type: description.type,
-      sdp: description.sdp
-    };
-    if (description.type === 'offer') {
-      pc._updateSignalingState('have-remote-offer');
-    } else {
-      pc._updateSignalingState('stable');
-    }
-    Object.keys(streams).forEach(function(sid) {
-      var stream = streams[sid];
-      if (stream.getTracks().length) {
-        if (pc.remoteStreams.indexOf(stream) === -1) {
-          pc.remoteStreams.push(stream);
-          var event = new Event('addstream');
-          event.stream = stream;
-          window.setTimeout(function() {
-            pc._dispatchEvent('addstream', event);
-          });
-        }
-
-        receiverList.forEach(function(item) {
-          var track = item[0];
-          var receiver = item[1];
-          if (stream.id !== item[2].id) {
-            return;
-          }
-          fireAddTrack(pc, track, receiver, [stream]);
-        });
-      }
-    });
-    receiverList.forEach(function(item) {
-      if (item[2]) {
-        return;
-      }
-      fireAddTrack(pc, item[0], item[1], []);
-    });
-
-    // check whether addIceCandidate({}) was called within four seconds after
-    // setRemoteDescription.
-    window.setTimeout(function() {
-      if (!(pc && pc.transceivers)) {
-        return;
-      }
-      pc.transceivers.forEach(function(transceiver) {
-        if (transceiver.iceTransport &&
-            transceiver.iceTransport.state === 'new' &&
-            transceiver.iceTransport.getRemoteCandidates().length > 0) {
-          console.warn('Timeout for addRemoteCandidate. Consider sending ' +
-              'an end-of-candidates notification');
-          transceiver.iceTransport.addRemoteCandidate({});
-        }
-      });
-    }, 4000);
-
-    return Promise.resolve();
-  };
-
-  RTCPeerConnection.prototype.close = function() {
-    this.transceivers.forEach(function(transceiver) {
-      /* not yet
-      if (transceiver.iceGatherer) {
-        transceiver.iceGatherer.close();
-      }
-      */
-      if (transceiver.iceTransport) {
-        transceiver.iceTransport.stop();
-      }
-      if (transceiver.dtlsTransport) {
-        transceiver.dtlsTransport.stop();
-      }
-      if (transceiver.rtpSender) {
-        transceiver.rtpSender.stop();
-      }
-      if (transceiver.rtpReceiver) {
-        transceiver.rtpReceiver.stop();
-      }
-    });
-    // FIXME: clean up tracks, local streams, remote streams, etc
-    this._isClosed = true;
-    this._updateSignalingState('closed');
-  };
-
-  // Update the signaling state.
-  RTCPeerConnection.prototype._updateSignalingState = function(newState) {
-    this.signalingState = newState;
-    var event = new Event('signalingstatechange');
-    this._dispatchEvent('signalingstatechange', event);
-  };
-
-  // Determine whether to fire the negotiationneeded event.
-  RTCPeerConnection.prototype._maybeFireNegotiationNeeded = function() {
-    var pc = this;
-    if (this.signalingState !== 'stable' || this.needNegotiation === true) {
-      return;
-    }
-    this.needNegotiation = true;
-    window.setTimeout(function() {
-      if (pc.needNegotiation) {
-        pc.needNegotiation = false;
-        var event = new Event('negotiationneeded');
-        pc._dispatchEvent('negotiationneeded', event);
-      }
-    }, 0);
-  };
-
-  // Update the ice connection state.
-  RTCPeerConnection.prototype._updateIceConnectionState = function() {
-    var newState;
-    var states = {
-      'new': 0,
-      closed: 0,
-      checking: 0,
-      connected: 0,
-      completed: 0,
-      disconnected: 0,
-      failed: 0
-    };
-    this.transceivers.forEach(function(transceiver) {
-      states[transceiver.iceTransport.state]++;
-    });
-
-    newState = 'new';
-    if (states.failed > 0) {
-      newState = 'failed';
-    } else if (states.checking > 0) {
-      newState = 'checking';
-    } else if (states.disconnected > 0) {
-      newState = 'disconnected';
-    } else if (states.new > 0) {
-      newState = 'new';
-    } else if (states.connected > 0) {
-      newState = 'connected';
-    } else if (states.completed > 0) {
-      newState = 'completed';
-    }
-
-    if (newState !== this.iceConnectionState) {
-      this.iceConnectionState = newState;
-      var event = new Event('iceconnectionstatechange');
-      this._dispatchEvent('iceconnectionstatechange', event);
-    }
-  };
-
-  // Update the connection state.
-  RTCPeerConnection.prototype._updateConnectionState = function() {
-    var newState;
-    var states = {
-      'new': 0,
-      closed: 0,
-      connecting: 0,
-      connected: 0,
-      completed: 0,
-      disconnected: 0,
-      failed: 0
-    };
-    this.transceivers.forEach(function(transceiver) {
-      states[transceiver.iceTransport.state]++;
-      states[transceiver.dtlsTransport.state]++;
-    });
-    // ICETransport.completed and connected are the same for this purpose.
-    states.connected += states.completed;
-
-    newState = 'new';
-    if (states.failed > 0) {
-      newState = 'failed';
-    } else if (states.connecting > 0) {
-      newState = 'connecting';
-    } else if (states.disconnected > 0) {
-      newState = 'disconnected';
-    } else if (states.new > 0) {
-      newState = 'new';
-    } else if (states.connected > 0) {
-      newState = 'connected';
-    }
-
-    if (newState !== this.connectionState) {
-      this.connectionState = newState;
-      var event = new Event('connectionstatechange');
-      this._dispatchEvent('connectionstatechange', event);
-    }
-  };
-
-  RTCPeerConnection.prototype.createOffer = function() {
-    var pc = this;
-
-    if (pc._isClosed) {
-      return Promise.reject(makeError('InvalidStateError',
-          'Can not call createOffer after close'));
-    }
-
-    var numAudioTracks = pc.transceivers.filter(function(t) {
-      return t.kind === 'audio';
-    }).length;
-    var numVideoTracks = pc.transceivers.filter(function(t) {
-      return t.kind === 'video';
-    }).length;
-
-    // Determine number of audio and video tracks we need to send/recv.
-    var offerOptions = arguments[0];
-    if (offerOptions) {
-      // Reject Chrome legacy constraints.
-      if (offerOptions.mandatory || offerOptions.optional) {
-        throw new TypeError(
-            'Legacy mandatory/optional constraints not supported.');
-      }
-      if (offerOptions.offerToReceiveAudio !== undefined) {
-        if (offerOptions.offerToReceiveAudio === true) {
-          numAudioTracks = 1;
-        } else if (offerOptions.offerToReceiveAudio === false) {
-          numAudioTracks = 0;
-        } else {
-          numAudioTracks = offerOptions.offerToReceiveAudio;
-        }
-      }
-      if (offerOptions.offerToReceiveVideo !== undefined) {
-        if (offerOptions.offerToReceiveVideo === true) {
-          numVideoTracks = 1;
-        } else if (offerOptions.offerToReceiveVideo === false) {
-          numVideoTracks = 0;
-        } else {
-          numVideoTracks = offerOptions.offerToReceiveVideo;
-        }
-      }
-    }
-
-    pc.transceivers.forEach(function(transceiver) {
-      if (transceiver.kind === 'audio') {
-        numAudioTracks--;
-        if (numAudioTracks < 0) {
-          transceiver.wantReceive = false;
-        }
-      } else if (transceiver.kind === 'video') {
-        numVideoTracks--;
-        if (numVideoTracks < 0) {
-          transceiver.wantReceive = false;
-        }
-      }
-    });
-
-    // Create M-lines for recvonly streams.
-    while (numAudioTracks > 0 || numVideoTracks > 0) {
-      if (numAudioTracks > 0) {
-        pc._createTransceiver('audio');
-        numAudioTracks--;
-      }
-      if (numVideoTracks > 0) {
-        pc._createTransceiver('video');
-        numVideoTracks--;
-      }
-    }
-
-    var sdp = SDPUtils.writeSessionBoilerplate(pc._sdpSessionId,
-        pc._sdpSessionVersion++);
-    pc.transceivers.forEach(function(transceiver, sdpMLineIndex) {
-      // For each track, create an ice gatherer, ice transport,
-      // dtls transport, potentially rtpsender and rtpreceiver.
-      var track = transceiver.track;
-      var kind = transceiver.kind;
-      var mid = transceiver.mid || SDPUtils.generateIdentifier();
-      transceiver.mid = mid;
-
-      if (!transceiver.iceGatherer) {
-        transceiver.iceGatherer = pc._createIceGatherer(sdpMLineIndex,
-            pc.usingBundle);
-      }
-
-      var localCapabilities = window.RTCRtpSender.getCapabilities(kind);
-      // filter RTX until additional stuff needed for RTX is implemented
-      // in adapter.js
-      if (edgeVersion < 15019) {
-        localCapabilities.codecs = localCapabilities.codecs.filter(
-            function(codec) {
-              return codec.name !== 'rtx';
-            });
-      }
-      localCapabilities.codecs.forEach(function(codec) {
-        // work around https://bugs.chromium.org/p/webrtc/issues/detail?id=6552
-        // by adding level-asymmetry-allowed=1
-        if (codec.name === 'H264' &&
-            codec.parameters['level-asymmetry-allowed'] === undefined) {
-          codec.parameters['level-asymmetry-allowed'] = '1';
-        }
-
-        // for subsequent offers, we might have to re-use the payload
-        // type of the last offer.
-        if (transceiver.remoteCapabilities &&
-            transceiver.remoteCapabilities.codecs) {
-          transceiver.remoteCapabilities.codecs.forEach(function(remoteCodec) {
-            if (codec.name.toLowerCase() === remoteCodec.name.toLowerCase() &&
-                codec.clockRate === remoteCodec.clockRate) {
-              codec.preferredPayloadType = remoteCodec.payloadType;
-            }
-          });
-        }
-      });
-      localCapabilities.headerExtensions.forEach(function(hdrExt) {
-        var remoteExtensions = transceiver.remoteCapabilities &&
-            transceiver.remoteCapabilities.headerExtensions || [];
-        remoteExtensions.forEach(function(rHdrExt) {
-          if (hdrExt.uri === rHdrExt.uri) {
-            hdrExt.id = rHdrExt.id;
-          }
-        });
-      });
-
-      // generate an ssrc now, to be used later in rtpSender.send
-      var sendEncodingParameters = transceiver.sendEncodingParameters || [{
-        ssrc: (2 * sdpMLineIndex + 1) * 1001
-      }];
-      if (track) {
-        // add RTX
-        if (edgeVersion >= 15019 && kind === 'video' &&
-            !sendEncodingParameters[0].rtx) {
-          sendEncodingParameters[0].rtx = {
-            ssrc: sendEncodingParameters[0].ssrc + 1
-          };
-        }
-      }
-
-      if (transceiver.wantReceive) {
-        transceiver.rtpReceiver = new window.RTCRtpReceiver(
-            transceiver.dtlsTransport, kind);
-      }
-
-      transceiver.localCapabilities = localCapabilities;
-      transceiver.sendEncodingParameters = sendEncodingParameters;
-    });
-
-    // always offer BUNDLE and dispose on return if not supported.
-    if (pc._config.bundlePolicy !== 'max-compat') {
-      sdp += 'a=group:BUNDLE ' + pc.transceivers.map(function(t) {
-        return t.mid;
-      }).join(' ') + '\r\n';
-    }
-    sdp += 'a=ice-options:trickle\r\n';
-
-    pc.transceivers.forEach(function(transceiver, sdpMLineIndex) {
-      sdp += writeMediaSection(transceiver, transceiver.localCapabilities,
-          'offer', transceiver.stream, pc._dtlsRole);
-      sdp += 'a=rtcp-rsize\r\n';
-
-      if (transceiver.iceGatherer && pc.iceGatheringState !== 'new' &&
-          (sdpMLineIndex === 0 || !pc.usingBundle)) {
-        transceiver.iceGatherer.getLocalCandidates().forEach(function(cand) {
-          cand.component = 1;
-          sdp += 'a=' + SDPUtils.writeCandidate(cand) + '\r\n';
-        });
-
-        if (transceiver.iceGatherer.state === 'completed') {
-          sdp += 'a=end-of-candidates\r\n';
-        }
-      }
-    });
-
-    var desc = new window.RTCSessionDescription({
-      type: 'offer',
-      sdp: sdp
-    });
-    return Promise.resolve(desc);
-  };
-
-  RTCPeerConnection.prototype.createAnswer = function() {
-    var pc = this;
-
-    if (pc._isClosed) {
-      return Promise.reject(makeError('InvalidStateError',
-          'Can not call createAnswer after close'));
-    }
-
-    if (!(pc.signalingState === 'have-remote-offer' ||
-        pc.signalingState === 'have-local-pranswer')) {
-      return Promise.reject(makeError('InvalidStateError',
-          'Can not call createAnswer in signalingState ' + pc.signalingState));
-    }
-
-    var sdp = SDPUtils.writeSessionBoilerplate(pc._sdpSessionId,
-        pc._sdpSessionVersion++);
-    if (pc.usingBundle) {
-      sdp += 'a=group:BUNDLE ' + pc.transceivers.map(function(t) {
-        return t.mid;
-      }).join(' ') + '\r\n';
-    }
-    var mediaSectionsInOffer = SDPUtils.getMediaSections(
-        pc._remoteDescription.sdp).length;
-    pc.transceivers.forEach(function(transceiver, sdpMLineIndex) {
-      if (sdpMLineIndex + 1 > mediaSectionsInOffer) {
-        return;
-      }
-      if (transceiver.rejected) {
-        if (transceiver.kind === 'application') {
-          if (transceiver.protocol === 'DTLS/SCTP') { // legacy fmt
-            sdp += 'm=application 0 DTLS/SCTP 5000\r\n';
-          } else {
-            sdp += 'm=application 0 ' + transceiver.protocol +
-                ' webrtc-datachannel\r\n';
-          }
-        } else if (transceiver.kind === 'audio') {
-          sdp += 'm=audio 0 UDP/TLS/RTP/SAVPF 0\r\n' +
-              'a=rtpmap:0 PCMU/8000\r\n';
-        } else if (transceiver.kind === 'video') {
-          sdp += 'm=video 0 UDP/TLS/RTP/SAVPF 120\r\n' +
-              'a=rtpmap:120 VP8/90000\r\n';
-        }
-        sdp += 'c=IN IP4 0.0.0.0\r\n' +
-            'a=inactive\r\n' +
-            'a=mid:' + transceiver.mid + '\r\n';
-        return;
-      }
-
-      // FIXME: look at direction.
-      if (transceiver.stream) {
-        var localTrack;
-        if (transceiver.kind === 'audio') {
-          localTrack = transceiver.stream.getAudioTracks()[0];
-        } else if (transceiver.kind === 'video') {
-          localTrack = transceiver.stream.getVideoTracks()[0];
-        }
-        if (localTrack) {
-          // add RTX
-          if (edgeVersion >= 15019 && transceiver.kind === 'video' &&
-              !transceiver.sendEncodingParameters[0].rtx) {
-            transceiver.sendEncodingParameters[0].rtx = {
-              ssrc: transceiver.sendEncodingParameters[0].ssrc + 1
-            };
-          }
-        }
-      }
-
-      // Calculate intersection of capabilities.
-      var commonCapabilities = getCommonCapabilities(
-          transceiver.localCapabilities,
-          transceiver.remoteCapabilities);
-
-      var hasRtx = commonCapabilities.codecs.filter(function(c) {
-        return c.name.toLowerCase() === 'rtx';
-      }).length;
-      if (!hasRtx && transceiver.sendEncodingParameters[0].rtx) {
-        delete transceiver.sendEncodingParameters[0].rtx;
-      }
-
-      sdp += writeMediaSection(transceiver, commonCapabilities,
-          'answer', transceiver.stream, pc._dtlsRole);
-      if (transceiver.rtcpParameters &&
-          transceiver.rtcpParameters.reducedSize) {
-        sdp += 'a=rtcp-rsize\r\n';
-      }
-    });
-
-    var desc = new window.RTCSessionDescription({
-      type: 'answer',
-      sdp: sdp
-    });
-    return Promise.resolve(desc);
-  };
-
-  RTCPeerConnection.prototype.addIceCandidate = function(candidate) {
-    var pc = this;
-    var sections;
-    if (candidate && !(candidate.sdpMLineIndex !== undefined ||
-        candidate.sdpMid)) {
-      return Promise.reject(new TypeError('sdpMLineIndex or sdpMid required'));
-    }
-
-    // TODO: needs to go into ops queue.
-    return new Promise(function(resolve, reject) {
-      if (!pc._remoteDescription) {
-        return reject(makeError('InvalidStateError',
-            'Can not add ICE candidate without a remote description'));
-      } else if (!candidate || candidate.candidate === '') {
-        for (var j = 0; j < pc.transceivers.length; j++) {
-          if (pc.transceivers[j].rejected) {
-            continue;
-          }
-          pc.transceivers[j].iceTransport.addRemoteCandidate({});
-          sections = SDPUtils.getMediaSections(pc._remoteDescription.sdp);
-          sections[j] += 'a=end-of-candidates\r\n';
-          pc._remoteDescription.sdp =
-              SDPUtils.getDescription(pc._remoteDescription.sdp) +
-              sections.join('');
-          if (pc.usingBundle) {
-            break;
-          }
-        }
-      } else {
-        var sdpMLineIndex = candidate.sdpMLineIndex;
-        if (candidate.sdpMid) {
-          for (var i = 0; i < pc.transceivers.length; i++) {
-            if (pc.transceivers[i].mid === candidate.sdpMid) {
-              sdpMLineIndex = i;
-              break;
-            }
-          }
-        }
-        var transceiver = pc.transceivers[sdpMLineIndex];
-        if (transceiver) {
-          if (transceiver.rejected) {
-            return resolve();
-          }
-          var cand = Object.keys(candidate.candidate).length > 0 ?
-              SDPUtils.parseCandidate(candidate.candidate) : {};
-          // Ignore Chrome's invalid candidates since Edge does not like them.
-          if (cand.protocol === 'tcp' && (cand.port === 0 || cand.port === 9)) {
-            return resolve();
-          }
-          // Ignore RTCP candidates, we assume RTCP-MUX.
-          if (cand.component && cand.component !== 1) {
-            return resolve();
-          }
-          // when using bundle, avoid adding candidates to the wrong
-          // ice transport. And avoid adding candidates added in the SDP.
-          if (sdpMLineIndex === 0 || (sdpMLineIndex > 0 &&
-              transceiver.iceTransport !== pc.transceivers[0].iceTransport)) {
-            if (!maybeAddCandidate(transceiver.iceTransport, cand)) {
-              return reject(makeError('OperationError',
-                  'Can not add ICE candidate'));
-            }
-          }
-
-          // update the remoteDescription.
-          var candidateString = candidate.candidate.trim();
-          if (candidateString.indexOf('a=') === 0) {
-            candidateString = candidateString.substr(2);
-          }
-          sections = SDPUtils.getMediaSections(pc._remoteDescription.sdp);
-          sections[sdpMLineIndex] += 'a=' +
-              (cand.type ? candidateString : 'end-of-candidates')
-              + '\r\n';
-          pc._remoteDescription.sdp =
-              SDPUtils.getDescription(pc._remoteDescription.sdp) +
-              sections.join('');
-        } else {
-          return reject(makeError('OperationError',
-              'Can not add ICE candidate'));
-        }
-      }
-      resolve();
-    });
-  };
-
-  RTCPeerConnection.prototype.getStats = function(selector) {
-    if (selector && selector instanceof window.MediaStreamTrack) {
-      var senderOrReceiver = null;
-      this.transceivers.forEach(function(transceiver) {
-        if (transceiver.rtpSender &&
-            transceiver.rtpSender.track === selector) {
-          senderOrReceiver = transceiver.rtpSender;
-        } else if (transceiver.rtpReceiver &&
-            transceiver.rtpReceiver.track === selector) {
-          senderOrReceiver = transceiver.rtpReceiver;
-        }
-      });
-      if (!senderOrReceiver) {
-        throw makeError('InvalidAccessError', 'Invalid selector.');
-      }
-      return senderOrReceiver.getStats();
-    }
-
-    var promises = [];
-    this.transceivers.forEach(function(transceiver) {
-      ['rtpSender', 'rtpReceiver', 'iceGatherer', 'iceTransport',
-          'dtlsTransport'].forEach(function(method) {
-            if (transceiver[method]) {
-              promises.push(transceiver[method].getStats());
-            }
-          });
-    });
-    return Promise.all(promises).then(function(allStats) {
-      var results = new Map();
-      allStats.forEach(function(stats) {
-        stats.forEach(function(stat) {
-          results.set(stat.id, stat);
-        });
-      });
-      return results;
-    });
-  };
-
-  // fix low-level stat names and return Map instead of object.
-  var ortcObjects = ['RTCRtpSender', 'RTCRtpReceiver', 'RTCIceGatherer',
-    'RTCIceTransport', 'RTCDtlsTransport'];
-  ortcObjects.forEach(function(ortcObjectName) {
-    var obj = window[ortcObjectName];
-    if (obj && obj.prototype && obj.prototype.getStats) {
-      var nativeGetstats = obj.prototype.getStats;
-      obj.prototype.getStats = function() {
-        return nativeGetstats.apply(this)
-        .then(function(nativeStats) {
-          var mapStats = new Map();
-          Object.keys(nativeStats).forEach(function(id) {
-            nativeStats[id].type = fixStatsType(nativeStats[id]);
-            mapStats.set(id, nativeStats[id]);
-          });
-          return mapStats;
-        });
-      };
-    }
-  });
-
-  // legacy callback shims. Should be moved to adapter.js some days.
-  var methods = ['createOffer', 'createAnswer'];
-  methods.forEach(function(method) {
-    var nativeMethod = RTCPeerConnection.prototype[method];
-    RTCPeerConnection.prototype[method] = function() {
-      var args = arguments;
-      if (typeof args[0] === 'function' ||
-          typeof args[1] === 'function') { // legacy
-        return nativeMethod.apply(this, [arguments[2]])
-        .then(function(description) {
-          if (typeof args[0] === 'function') {
-            args[0].apply(null, [description]);
-          }
-        }, function(error) {
-          if (typeof args[1] === 'function') {
-            args[1].apply(null, [error]);
-          }
-        });
-      }
-      return nativeMethod.apply(this, arguments);
-    };
-  });
-
-  methods = ['setLocalDescription', 'setRemoteDescription', 'addIceCandidate'];
-  methods.forEach(function(method) {
-    var nativeMethod = RTCPeerConnection.prototype[method];
-    RTCPeerConnection.prototype[method] = function() {
-      var args = arguments;
-      if (typeof args[1] === 'function' ||
-          typeof args[2] === 'function') { // legacy
-        return nativeMethod.apply(this, arguments)
-        .then(function() {
-          if (typeof args[1] === 'function') {
-            args[1].apply(null);
-          }
-        }, function(error) {
-          if (typeof args[2] === 'function') {
-            args[2].apply(null, [error]);
-          }
-        });
-      }
-      return nativeMethod.apply(this, arguments);
-    };
-  });
-
-  // getStats is special. It doesn't have a spec legacy method yet we support
-  // getStats(something, cb) without error callbacks.
-  ['getStats'].forEach(function(method) {
-    var nativeMethod = RTCPeerConnection.prototype[method];
-    RTCPeerConnection.prototype[method] = function() {
-      var args = arguments;
-      if (typeof args[1] === 'function') {
-        return nativeMethod.apply(this, arguments)
-        .then(function() {
-          if (typeof args[1] === 'function') {
-            args[1].apply(null);
-          }
-        });
-      }
-      return nativeMethod.apply(this, arguments);
-    };
-  });
-
-  return RTCPeerConnection;
-};
-
-},{"sdp":15}],15:[function(require,module,exports){
- /* eslint-env node */
-'use strict';
-
-// SDP helpers.
-var SDPUtils = {};
-
-// Generate an alphanumeric identifier for cname or mids.
-// TODO: use UUIDs instead? https://gist.github.com/jed/982883
-SDPUtils.generateIdentifier = function() {
-  return Math.random().toString(36).substr(2, 10);
-};
-
-// The RTCP CNAME used by all peerconnections from the same JS.
-SDPUtils.localCName = SDPUtils.generateIdentifier();
-
-// Splits SDP into lines, dealing with both CRLF and LF.
-SDPUtils.splitLines = function(blob) {
-  return blob.trim().split('\n').map(function(line) {
-    return line.trim();
-  });
-};
-// Splits SDP into sessionpart and mediasections. Ensures CRLF.
-SDPUtils.splitSections = function(blob) {
-  var parts = blob.split('\nm=');
-  return parts.map(function(part, index) {
-    return (index > 0 ? 'm=' + part : part).trim() + '\r\n';
-  });
-};
-
-// returns the session description.
-SDPUtils.getDescription = function(blob) {
-  var sections = SDPUtils.splitSections(blob);
-  return sections && sections[0];
-};
-
-// returns the individual media sections.
-SDPUtils.getMediaSections = function(blob) {
-  var sections = SDPUtils.splitSections(blob);
-  sections.shift();
-  return sections;
-};
-
-// Returns lines that start with a certain prefix.
-SDPUtils.matchPrefix = function(blob, prefix) {
-  return SDPUtils.splitLines(blob).filter(function(line) {
-    return line.indexOf(prefix) === 0;
-  });
-};
-
-// Parses an ICE candidate line. Sample input:
-// candidate:702786350 2 udp 41819902 8.8.8.8 60769 typ relay raddr 8.8.8.8
-// rport 55996"
-SDPUtils.parseCandidate = function(line) {
-  var parts;
-  // Parse both variants.
-  if (line.indexOf('a=candidate:') === 0) {
-    parts = line.substring(12).split(' ');
-  } else {
-    parts = line.substring(10).split(' ');
-  }
-
-  var candidate = {
-    foundation: parts[0],
-    component: parseInt(parts[1], 10),
-    protocol: parts[2].toLowerCase(),
-    priority: parseInt(parts[3], 10),
-    ip: parts[4],
-    port: parseInt(parts[5], 10),
-    // skip parts[6] == 'typ'
-    type: parts[7]
-  };
-
-  for (var i = 8; i < parts.length; i += 2) {
-    switch (parts[i]) {
-      case 'raddr':
-        candidate.relatedAddress = parts[i + 1];
-        break;
-      case 'rport':
-        candidate.relatedPort = parseInt(parts[i + 1], 10);
-        break;
-      case 'tcptype':
-        candidate.tcpType = parts[i + 1];
-        break;
-      case 'ufrag':
-        candidate.ufrag = parts[i + 1]; // for backward compability.
-        candidate.usernameFragment = parts[i + 1];
-        break;
-      default: // extension handling, in particular ufrag
-        candidate[parts[i]] = parts[i + 1];
-        break;
-    }
-  }
-  return candidate;
-};
-
-// Translates a candidate object into SDP candidate attribute.
-SDPUtils.writeCandidate = function(candidate) {
-  var sdp = [];
-  sdp.push(candidate.foundation);
-  sdp.push(candidate.component);
-  sdp.push(candidate.protocol.toUpperCase());
-  sdp.push(candidate.priority);
-  sdp.push(candidate.ip);
-  sdp.push(candidate.port);
-
-  var type = candidate.type;
-  sdp.push('typ');
-  sdp.push(type);
-  if (type !== 'host' && candidate.relatedAddress &&
-      candidate.relatedPort) {
-    sdp.push('raddr');
-    sdp.push(candidate.relatedAddress);
-    sdp.push('rport');
-    sdp.push(candidate.relatedPort);
-  }
-  if (candidate.tcpType && candidate.protocol.toLowerCase() === 'tcp') {
-    sdp.push('tcptype');
-    sdp.push(candidate.tcpType);
-  }
-  if (candidate.usernameFragment || candidate.ufrag) {
-    sdp.push('ufrag');
-    sdp.push(candidate.usernameFragment || candidate.ufrag);
-  }
-  return 'candidate:' + sdp.join(' ');
-};
-
-// Parses an ice-options line, returns an array of option tags.
-// a=ice-options:foo bar
-SDPUtils.parseIceOptions = function(line) {
-  return line.substr(14).split(' ');
-};
-
-// Parses an rtpmap line, returns RTCRtpCoddecParameters. Sample input:
-// a=rtpmap:111 opus/48000/2
-SDPUtils.parseRtpMap = function(line) {
-  var parts = line.substr(9).split(' ');
-  var parsed = {
-    payloadType: parseInt(parts.shift(), 10) // was: id
-  };
-
-  parts = parts[0].split('/');
-
-  parsed.name = parts[0];
-  parsed.clockRate = parseInt(parts[1], 10); // was: clockrate
-  parsed.channels = parts.length === 3 ? parseInt(parts[2], 10) : 1;
-  // legacy alias, got renamed back to channels in ORTC.
-  parsed.numChannels = parsed.channels;
-  return parsed;
-};
-
-// Generate an a=rtpmap line from RTCRtpCodecCapability or
-// RTCRtpCodecParameters.
-SDPUtils.writeRtpMap = function(codec) {
-  var pt = codec.payloadType;
-  if (codec.preferredPayloadType !== undefined) {
-    pt = codec.preferredPayloadType;
-  }
-  var channels = codec.channels || codec.numChannels || 1;
-  return 'a=rtpmap:' + pt + ' ' + codec.name + '/' + codec.clockRate +
-      (channels !== 1 ? '/' + channels : '') + '\r\n';
-};
-
-// Parses an a=extmap line (headerextension from RFC 5285). Sample input:
-// a=extmap:2 urn:ietf:params:rtp-hdrext:toffset
-// a=extmap:2/sendonly urn:ietf:params:rtp-hdrext:toffset
-SDPUtils.parseExtmap = function(line) {
-  var parts = line.substr(9).split(' ');
-  return {
-    id: parseInt(parts[0], 10),
-    direction: parts[0].indexOf('/') > 0 ? parts[0].split('/')[1] : 'sendrecv',
-    uri: parts[1]
-  };
-};
-
-// Generates a=extmap line from RTCRtpHeaderExtensionParameters or
-// RTCRtpHeaderExtension.
-SDPUtils.writeExtmap = function(headerExtension) {
-  return 'a=extmap:' + (headerExtension.id || headerExtension.preferredId) +
-      (headerExtension.direction && headerExtension.direction !== 'sendrecv'
-          ? '/' + headerExtension.direction
-          : '') +
-      ' ' + headerExtension.uri + '\r\n';
-};
-
-// Parses an ftmp line, returns dictionary. Sample input:
-// a=fmtp:96 vbr=on;cng=on
-// Also deals with vbr=on; cng=on
-SDPUtils.parseFmtp = function(line) {
-  var parsed = {};
-  var kv;
-  var parts = line.substr(line.indexOf(' ') + 1).split(';');
-  for (var j = 0; j < parts.length; j++) {
-    kv = parts[j].trim().split('=');
-    parsed[kv[0].trim()] = kv[1];
-  }
-  return parsed;
-};
-
-// Generates an a=ftmp line from RTCRtpCodecCapability or RTCRtpCodecParameters.
-SDPUtils.writeFmtp = function(codec) {
-  var line = '';
-  var pt = codec.payloadType;
-  if (codec.preferredPayloadType !== undefined) {
-    pt = codec.preferredPayloadType;
-  }
-  if (codec.parameters && Object.keys(codec.parameters).length) {
-    var params = [];
-    Object.keys(codec.parameters).forEach(function(param) {
-      if (codec.parameters[param]) {
-        params.push(param + '=' + codec.parameters[param]);
-      } else {
-        params.push(param);
-      }
-    });
-    line += 'a=fmtp:' + pt + ' ' + params.join(';') + '\r\n';
-  }
-  return line;
-};
-
-// Parses an rtcp-fb line, returns RTCPRtcpFeedback object. Sample input:
-// a=rtcp-fb:98 nack rpsi
-SDPUtils.parseRtcpFb = function(line) {
-  var parts = line.substr(line.indexOf(' ') + 1).split(' ');
-  return {
-    type: parts.shift(),
-    parameter: parts.join(' ')
-  };
-};
-// Generate a=rtcp-fb lines from RTCRtpCodecCapability or RTCRtpCodecParameters.
-SDPUtils.writeRtcpFb = function(codec) {
-  var lines = '';
-  var pt = codec.payloadType;
-  if (codec.preferredPayloadType !== undefined) {
-    pt = codec.preferredPayloadType;
-  }
-  if (codec.rtcpFeedback && codec.rtcpFeedback.length) {
-    // FIXME: special handling for trr-int?
-    codec.rtcpFeedback.forEach(function(fb) {
-      lines += 'a=rtcp-fb:' + pt + ' ' + fb.type +
-      (fb.parameter && fb.parameter.length ? ' ' + fb.parameter : '') +
-          '\r\n';
-    });
-  }
-  return lines;
-};
-
-// Parses an RFC 5576 ssrc media attribute. Sample input:
-// a=ssrc:3735928559 cname:something
-SDPUtils.parseSsrcMedia = function(line) {
-  var sp = line.indexOf(' ');
-  var parts = {
-    ssrc: parseInt(line.substr(7, sp - 7), 10)
-  };
-  var colon = line.indexOf(':', sp);
-  if (colon > -1) {
-    parts.attribute = line.substr(sp + 1, colon - sp - 1);
-    parts.value = line.substr(colon + 1);
-  } else {
-    parts.attribute = line.substr(sp + 1);
-  }
-  return parts;
-};
-
-SDPUtils.parseSsrcGroup = function(line) {
-  var parts = line.substr(13).split(' ');
-  return {
-    semantics: parts.shift(),
-    ssrcs: parts.map(function(ssrc) {
-      return parseInt(ssrc, 10);
-    })
-  };
-};
-
-// Extracts the MID (RFC 5888) from a media section.
-// returns the MID or undefined if no mid line was found.
-SDPUtils.getMid = function(mediaSection) {
-  var mid = SDPUtils.matchPrefix(mediaSection, 'a=mid:')[0];
-  if (mid) {
-    return mid.substr(6);
-  }
-};
-
-SDPUtils.parseFingerprint = function(line) {
-  var parts = line.substr(14).split(' ');
-  return {
-    algorithm: parts[0].toLowerCase(), // algorithm is case-sensitive in Edge.
-    value: parts[1]
-  };
-};
-
-// Extracts DTLS parameters from SDP media section or sessionpart.
-// FIXME: for consistency with other functions this should only
-//   get the fingerprint line as input. See also getIceParameters.
-SDPUtils.getDtlsParameters = function(mediaSection, sessionpart) {
-  var lines = SDPUtils.matchPrefix(mediaSection + sessionpart,
-      'a=fingerprint:');
-  // Note: a=setup line is ignored since we use the 'auto' role.
-  // Note2: 'algorithm' is not case sensitive except in Edge.
-  return {
-    role: 'auto',
-    fingerprints: lines.map(SDPUtils.parseFingerprint)
-  };
-};
-
-// Serializes DTLS parameters to SDP.
-SDPUtils.writeDtlsParameters = function(params, setupType) {
-  var sdp = 'a=setup:' + setupType + '\r\n';
-  params.fingerprints.forEach(function(fp) {
-    sdp += 'a=fingerprint:' + fp.algorithm + ' ' + fp.value + '\r\n';
-  });
-  return sdp;
-};
-// Parses ICE information from SDP media section or sessionpart.
-// FIXME: for consistency with other functions this should only
-//   get the ice-ufrag and ice-pwd lines as input.
-SDPUtils.getIceParameters = function(mediaSection, sessionpart) {
-  var lines = SDPUtils.splitLines(mediaSection);
-  // Search in session part, too.
-  lines = lines.concat(SDPUtils.splitLines(sessionpart));
-  var iceParameters = {
-    usernameFragment: lines.filter(function(line) {
-      return line.indexOf('a=ice-ufrag:') === 0;
-    })[0].substr(12),
-    password: lines.filter(function(line) {
-      return line.indexOf('a=ice-pwd:') === 0;
-    })[0].substr(10)
-  };
-  return iceParameters;
-};
-
-// Serializes ICE parameters to SDP.
-SDPUtils.writeIceParameters = function(params) {
-  return 'a=ice-ufrag:' + params.usernameFragment + '\r\n' +
-      'a=ice-pwd:' + params.password + '\r\n';
-};
-
-// Parses the SDP media section and returns RTCRtpParameters.
-SDPUtils.parseRtpParameters = function(mediaSection) {
-  var description = {
-    codecs: [],
-    headerExtensions: [],
-    fecMechanisms: [],
-    rtcp: []
-  };
-  var lines = SDPUtils.splitLines(mediaSection);
-  var mline = lines[0].split(' ');
-  for (var i = 3; i < mline.length; i++) { // find all codecs from mline[3..]
-    var pt = mline[i];
-    var rtpmapline = SDPUtils.matchPrefix(
-        mediaSection, 'a=rtpmap:' + pt + ' ')[0];
-    if (rtpmapline) {
-      var codec = SDPUtils.parseRtpMap(rtpmapline);
-      var fmtps = SDPUtils.matchPrefix(
-          mediaSection, 'a=fmtp:' + pt + ' ');
-      // Only the first a=fmtp:<pt> is considered.
-      codec.parameters = fmtps.length ? SDPUtils.parseFmtp(fmtps[0]) : {};
-      codec.rtcpFeedback = SDPUtils.matchPrefix(
-          mediaSection, 'a=rtcp-fb:' + pt + ' ')
-        .map(SDPUtils.parseRtcpFb);
-      description.codecs.push(codec);
-      // parse FEC mechanisms from rtpmap lines.
-      switch (codec.name.toUpperCase()) {
-        case 'RED':
-        case 'ULPFEC':
-          description.fecMechanisms.push(codec.name.toUpperCase());
-          break;
-        default: // only RED and ULPFEC are recognized as FEC mechanisms.
-          break;
-      }
-    }
-  }
-  SDPUtils.matchPrefix(mediaSection, 'a=extmap:').forEach(function(line) {
-    description.headerExtensions.push(SDPUtils.parseExtmap(line));
-  });
-  // FIXME: parse rtcp.
-  return description;
-};
-
-// Generates parts of the SDP media section describing the capabilities /
-// parameters.
-SDPUtils.writeRtpDescription = function(kind, caps) {
-  var sdp = '';
-
-  // Build the mline.
-  sdp += 'm=' + kind + ' ';
-  sdp += caps.codecs.length > 0 ? '9' : '0'; // reject if no codecs.
-  sdp += ' UDP/TLS/RTP/SAVPF ';
-  sdp += caps.codecs.map(function(codec) {
-    if (codec.preferredPayloadType !== undefined) {
-      return codec.preferredPayloadType;
-    }
-    return codec.payloadType;
-  }).join(' ') + '\r\n';
-
-  sdp += 'c=IN IP4 0.0.0.0\r\n';
-  sdp += 'a=rtcp:9 IN IP4 0.0.0.0\r\n';
-
-  // Add a=rtpmap lines for each codec. Also fmtp and rtcp-fb.
-  caps.codecs.forEach(function(codec) {
-    sdp += SDPUtils.writeRtpMap(codec);
-    sdp += SDPUtils.writeFmtp(codec);
-    sdp += SDPUtils.writeRtcpFb(codec);
-  });
-  var maxptime = 0;
-  caps.codecs.forEach(function(codec) {
-    if (codec.maxptime > maxptime) {
-      maxptime = codec.maxptime;
-    }
-  });
-  if (maxptime > 0) {
-    sdp += 'a=maxptime:' + maxptime + '\r\n';
-  }
-  sdp += 'a=rtcp-mux\r\n';
-
-  if (caps.headerExtensions) {
-    caps.headerExtensions.forEach(function(extension) {
-      sdp += SDPUtils.writeExtmap(extension);
-    });
-  }
-  // FIXME: write fecMechanisms.
-  return sdp;
-};
-
-// Parses the SDP media section and returns an array of
-// RTCRtpEncodingParameters.
-SDPUtils.parseRtpEncodingParameters = function(mediaSection) {
-  var encodingParameters = [];
-  var description = SDPUtils.parseRtpParameters(mediaSection);
-  var hasRed = description.fecMechanisms.indexOf('RED') !== -1;
-  var hasUlpfec = description.fecMechanisms.indexOf('ULPFEC') !== -1;
-
-  // filter a=ssrc:... cname:, ignore PlanB-msid
-  var ssrcs = SDPUtils.matchPrefix(mediaSection, 'a=ssrc:')
-  .map(function(line) {
-    return SDPUtils.parseSsrcMedia(line);
-  })
-  .filter(function(parts) {
-    return parts.attribute === 'cname';
-  });
-  var primarySsrc = ssrcs.length > 0 && ssrcs[0].ssrc;
-  var secondarySsrc;
-
-  var flows = SDPUtils.matchPrefix(mediaSection, 'a=ssrc-group:FID')
-  .map(function(line) {
-    var parts = line.substr(17).split(' ');
-    return parts.map(function(part) {
-      return parseInt(part, 10);
-    });
-  });
-  if (flows.length > 0 && flows[0].length > 1 && flows[0][0] === primarySsrc) {
-    secondarySsrc = flows[0][1];
-  }
-
-  description.codecs.forEach(function(codec) {
-    if (codec.name.toUpperCase() === 'RTX' && codec.parameters.apt) {
-      var encParam = {
-        ssrc: primarySsrc,
-        codecPayloadType: parseInt(codec.parameters.apt, 10)
-      };
-      if (primarySsrc && secondarySsrc) {
-        encParam.rtx = {ssrc: secondarySsrc};
-      }
-      encodingParameters.push(encParam);
-      if (hasRed) {
-        encParam = JSON.parse(JSON.stringify(encParam));
-        encParam.fec = {
-          ssrc: secondarySsrc,
-          mechanism: hasUlpfec ? 'red+ulpfec' : 'red'
-        };
-        encodingParameters.push(encParam);
-      }
-    }
-  });
-  if (encodingParameters.length === 0 && primarySsrc) {
-    encodingParameters.push({
-      ssrc: primarySsrc
-    });
-  }
-
-  // we support both b=AS and b=TIAS but interpret AS as TIAS.
-  var bandwidth = SDPUtils.matchPrefix(mediaSection, 'b=');
-  if (bandwidth.length) {
-    if (bandwidth[0].indexOf('b=TIAS:') === 0) {
-      bandwidth = parseInt(bandwidth[0].substr(7), 10);
-    } else if (bandwidth[0].indexOf('b=AS:') === 0) {
-      // use formula from JSEP to convert b=AS to TIAS value.
-      bandwidth = parseInt(bandwidth[0].substr(5), 10) * 1000 * 0.95
-          - (50 * 40 * 8);
-    } else {
-      bandwidth = undefined;
-    }
-    encodingParameters.forEach(function(params) {
-      params.maxBitrate = bandwidth;
-    });
-  }
-  return encodingParameters;
-};
-
-// parses http://draft.ortc.org/#rtcrtcpparameters*
-SDPUtils.parseRtcpParameters = function(mediaSection) {
-  var rtcpParameters = {};
-
-  // Gets the first SSRC. Note tha with RTX there might be multiple
-  // SSRCs.
-  var remoteSsrc = SDPUtils.matchPrefix(mediaSection, 'a=ssrc:')
-      .map(function(line) {
-        return SDPUtils.parseSsrcMedia(line);
-      })
-      .filter(function(obj) {
-        return obj.attribute === 'cname';
-      })[0];
-  if (remoteSsrc) {
-    rtcpParameters.cname = remoteSsrc.value;
-    rtcpParameters.ssrc = remoteSsrc.ssrc;
-  }
-
-  // Edge uses the compound attribute instead of reducedSize
-  // compound is !reducedSize
-  var rsize = SDPUtils.matchPrefix(mediaSection, 'a=rtcp-rsize');
-  rtcpParameters.reducedSize = rsize.length > 0;
-  rtcpParameters.compound = rsize.length === 0;
-
-  // parses the rtcp-mux attrіbute.
-  // Note that Edge does not support unmuxed RTCP.
-  var mux = SDPUtils.matchPrefix(mediaSection, 'a=rtcp-mux');
-  rtcpParameters.mux = mux.length > 0;
-
-  return rtcpParameters;
-};
-
-// parses either a=msid: or a=ssrc:... msid lines and returns
-// the id of the MediaStream and MediaStreamTrack.
-SDPUtils.parseMsid = function(mediaSection) {
-  var parts;
-  var spec = SDPUtils.matchPrefix(mediaSection, 'a=msid:');
-  if (spec.length === 1) {
-    parts = spec[0].substr(7).split(' ');
-    return {stream: parts[0], track: parts[1]};
-  }
-  var planB = SDPUtils.matchPrefix(mediaSection, 'a=ssrc:')
-  .map(function(line) {
-    return SDPUtils.parseSsrcMedia(line);
-  })
-  .filter(function(msidParts) {
-    return msidParts.attribute === 'msid';
-  });
-  if (planB.length > 0) {
-    parts = planB[0].value.split(' ');
-    return {stream: parts[0], track: parts[1]};
-  }
-};
-
-// Generate a session ID for SDP.
-// https://tools.ietf.org/html/draft-ietf-rtcweb-jsep-20#section-5.2.1
-// recommends using a cryptographically random +ve 64-bit value
-// but right now this should be acceptable and within the right range
-SDPUtils.generateSessionId = function() {
-  return Math.random().toString().substr(2, 21);
-};
-
-// Write boilder plate for start of SDP
-// sessId argument is optional - if not supplied it will
-// be generated randomly
-// sessVersion is optional and defaults to 2
-SDPUtils.writeSessionBoilerplate = function(sessId, sessVer) {
-  var sessionId;
-  var version = sessVer !== undefined ? sessVer : 2;
-  if (sessId) {
-    sessionId = sessId;
-  } else {
-    sessionId = SDPUtils.generateSessionId();
-  }
-  // FIXME: sess-id should be an NTP timestamp.
-  return 'v=0\r\n' +
-      'o=thisisadapterortc ' + sessionId + ' ' + version +
-        ' IN IP4 127.0.0.1\r\n' +
-      's=-\r\n' +
-      't=0 0\r\n';
-};
-
-SDPUtils.writeMediaSection = function(transceiver, caps, type, stream) {
-  var sdp = SDPUtils.writeRtpDescription(transceiver.kind, caps);
-
-  // Map ICE parameters (ufrag, pwd) to SDP.
-  sdp += SDPUtils.writeIceParameters(
-      transceiver.iceGatherer.getLocalParameters());
-
-  // Map DTLS parameters to SDP.
-  sdp += SDPUtils.writeDtlsParameters(
-      transceiver.dtlsTransport.getLocalParameters(),
-      type === 'offer' ? 'actpass' : 'active');
-
-  sdp += 'a=mid:' + transceiver.mid + '\r\n';
-
-  if (transceiver.direction) {
-    sdp += 'a=' + transceiver.direction + '\r\n';
-  } else if (transceiver.rtpSender && transceiver.rtpReceiver) {
-    sdp += 'a=sendrecv\r\n';
-  } else if (transceiver.rtpSender) {
-    sdp += 'a=sendonly\r\n';
-  } else if (transceiver.rtpReceiver) {
-    sdp += 'a=recvonly\r\n';
-  } else {
-    sdp += 'a=inactive\r\n';
-  }
-
-  if (transceiver.rtpSender) {
-    // spec.
-    var msid = 'msid:' + stream.id + ' ' +
-        transceiver.rtpSender.track.id + '\r\n';
-    sdp += 'a=' + msid;
-
-    // for Chrome.
-    sdp += 'a=ssrc:' + transceiver.sendEncodingParameters[0].ssrc +
-        ' ' + msid;
-    if (transceiver.sendEncodingParameters[0].rtx) {
-      sdp += 'a=ssrc:' + transceiver.sendEncodingParameters[0].rtx.ssrc +
-          ' ' + msid;
-      sdp += 'a=ssrc-group:FID ' +
-          transceiver.sendEncodingParameters[0].ssrc + ' ' +
-          transceiver.sendEncodingParameters[0].rtx.ssrc +
-          '\r\n';
-    }
-  }
-  // FIXME: this should be written by writeRtpDescription.
-  sdp += 'a=ssrc:' + transceiver.sendEncodingParameters[0].ssrc +
-      ' cname:' + SDPUtils.localCName + '\r\n';
-  if (transceiver.rtpSender && transceiver.sendEncodingParameters[0].rtx) {
-    sdp += 'a=ssrc:' + transceiver.sendEncodingParameters[0].rtx.ssrc +
-        ' cname:' + SDPUtils.localCName + '\r\n';
-  }
-  return sdp;
-};
-
-// Gets the direction from the mediaSection or the sessionpart.
-SDPUtils.getDirection = function(mediaSection, sessionpart) {
-  // Look for sendrecv, sendonly, recvonly, inactive, default to sendrecv.
-  var lines = SDPUtils.splitLines(mediaSection);
-  for (var i = 0; i < lines.length; i++) {
-    switch (lines[i]) {
-      case 'a=sendrecv':
-      case 'a=sendonly':
-      case 'a=recvonly':
-      case 'a=inactive':
-        return lines[i].substr(2);
-      default:
-        // FIXME: What should happen here?
-    }
-  }
-  if (sessionpart) {
-    return SDPUtils.getDirection(sessionpart);
-  }
-  return 'sendrecv';
-};
-
-SDPUtils.getKind = function(mediaSection) {
-  var lines = SDPUtils.splitLines(mediaSection);
-  var mline = lines[0].split(' ');
-  return mline[0].substr(2);
-};
-
-SDPUtils.isRejected = function(mediaSection) {
-  return mediaSection.split(' ', 2)[1] === '0';
-};
-
-SDPUtils.parseMLine = function(mediaSection) {
-  var lines = SDPUtils.splitLines(mediaSection);
-  var parts = lines[0].substr(2).split(' ');
-  return {
-    kind: parts[0],
-    port: parseInt(parts[1], 10),
-    protocol: parts[2],
-    fmt: parts.slice(3).join(' ')
-  };
-};
-
-SDPUtils.parseOLine = function(mediaSection) {
-  var line = SDPUtils.matchPrefix(mediaSection, 'o=')[0];
-  var parts = line.substr(2).split(' ');
-  return {
-    username: parts[0],
-    sessionId: parts[1],
-    sessionVersion: parseInt(parts[2], 10),
-    netType: parts[3],
-    addressType: parts[4],
-    address: parts[5]
-  };
-};
-
-// a very naive interpretation of a valid SDP.
-SDPUtils.isValidSDP = function(blob) {
-  if (typeof blob !== 'string' || blob.length === 0) {
-    return false;
-  }
-  var lines = SDPUtils.splitLines(blob);
-  for (var i = 0; i < lines.length; i++) {
-    if (lines[i].length < 2 || lines[i].charAt(1) !== '=') {
-      return false;
-    }
-    // TODO: check the modifier a bit more.
-  }
-  return true;
-};
-
-// Expose public methods.
-if (typeof module === 'object') {
-  module.exports = SDPUtils;
-}
-
-},{}],16:[function(require,module,exports){
-(function (global){
-/*
- *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree.
- */
- /* eslint-env node */
-
-'use strict';
-
-var adapterFactory = require('./adapter_factory.js');
-module.exports = adapterFactory({window: global.window});
-
-}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
-},{"./adapter_factory.js":17}],17:[function(require,module,exports){
-/*
- *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree.
- */
- /* eslint-env node */
-
-'use strict';
-
-var utils = require('./utils');
-// Shimming starts here.
-module.exports = function(dependencies, opts) {
-  var window = dependencies && dependencies.window;
-
-  var options = {
-    shimChrome: true,
-    shimFirefox: true,
-    shimEdge: true,
-    shimSafari: true,
-  };
-
-  for (var key in opts) {
-    if (hasOwnProperty.call(opts, key)) {
-      options[key] = opts[key];
-    }
-  }
-
-  // Utils.
-  var logging = utils.log;
-  var browserDetails = utils.detectBrowser(window);
-
-  // Uncomment the line below if you want logging to occur, including logging
-  // for the switch statement below. Can also be turned on in the browser via
-  // adapter.disableLog(false), but then logging from the switch statement below
-  // will not appear.
-  // require('./utils').disableLog(false);
-
-  // Browser shims.
-  var chromeShim = require('./chrome/chrome_shim') || null;
-  var edgeShim = require('./edge/edge_shim') || null;
-  var firefoxShim = require('./firefox/firefox_shim') || null;
-  var safariShim = require('./safari/safari_shim') || null;
-  var commonShim = require('./common_shim') || null;
-
-  // Export to the adapter global object visible in the browser.
-  var adapter = {
-    browserDetails: browserDetails,
-    commonShim: commonShim,
-    extractVersion: utils.extractVersion,
-    disableLog: utils.disableLog,
-    disableWarnings: utils.disableWarnings
-  };
-
-  // Shim browser if found.
-  switch (browserDetails.browser) {
-    case 'chrome':
-      if (!chromeShim || !chromeShim.shimPeerConnection ||
-          !options.shimChrome) {
-        logging('Chrome shim is not included in this adapter release.');
-        return adapter;
-      }
-      logging('adapter.js shimming chrome.');
-      // Export to the adapter global object visible in the browser.
-      adapter.browserShim = chromeShim;
-      commonShim.shimCreateObjectURL(window);
-
-      chromeShim.shimGetUserMedia(window);
-      chromeShim.shimMediaStream(window);
-      chromeShim.shimSourceObject(window);
-      chromeShim.shimPeerConnection(window);
-      chromeShim.shimOnTrack(window);
-      chromeShim.shimAddTrackRemoveTrack(window);
-      chromeShim.shimGetSendersWithDtmf(window);
-      chromeShim.shimSenderReceiverGetStats(window);
-      chromeShim.fixNegotiationNeeded(window);
-
-      commonShim.shimRTCIceCandidate(window);
-      commonShim.shimMaxMessageSize(window);
-      commonShim.shimSendThrowTypeError(window);
-      break;
-    case 'firefox':
-      if (!firefoxShim || !firefoxShim.shimPeerConnection ||
-          !options.shimFirefox) {
-        logging('Firefox shim is not included in this adapter release.');
-        return adapter;
-      }
-      logging('adapter.js shimming firefox.');
-      // Export to the adapter global object visible in the browser.
-      adapter.browserShim = firefoxShim;
-      commonShim.shimCreateObjectURL(window);
-
-      firefoxShim.shimGetUserMedia(window);
-      firefoxShim.shimSourceObject(window);
-      firefoxShim.shimPeerConnection(window);
-      firefoxShim.shimOnTrack(window);
-      firefoxShim.shimRemoveStream(window);
-      firefoxShim.shimSenderGetStats(window);
-      firefoxShim.shimReceiverGetStats(window);
-      firefoxShim.shimRTCDataChannel(window);
-
-      commonShim.shimRTCIceCandidate(window);
-      commonShim.shimMaxMessageSize(window);
-      commonShim.shimSendThrowTypeError(window);
-      break;
-    case 'edge':
-      if (!edgeShim || !edgeShim.shimPeerConnection || !options.shimEdge) {
-        logging('MS edge shim is not included in this adapter release.');
-        return adapter;
-      }
-      logging('adapter.js shimming edge.');
-      // Export to the adapter global object visible in the browser.
-      adapter.browserShim = edgeShim;
-      commonShim.shimCreateObjectURL(window);
-
-      edgeShim.shimGetUserMedia(window);
-      edgeShim.shimPeerConnection(window);
-      edgeShim.shimReplaceTrack(window);
-
-      // the edge shim implements the full RTCIceCandidate object.
-
-      commonShim.shimMaxMessageSize(window);
-      commonShim.shimSendThrowTypeError(window);
-      break;
-    case 'safari':
-      if (!safariShim || !options.shimSafari) {
-        logging('Safari shim is not included in this adapter release.');
-        return adapter;
-      }
-      logging('adapter.js shimming safari.');
-      // Export to the adapter global object visible in the browser.
-      adapter.browserShim = safariShim;
-      commonShim.shimCreateObjectURL(window);
-
-      safariShim.shimRTCIceServerUrls(window);
-      safariShim.shimCreateOfferLegacy(window);
-      safariShim.shimCallbacksAPI(window);
-      safariShim.shimLocalStreamsAPI(window);
-      safariShim.shimRemoteStreamsAPI(window);
-      safariShim.shimTrackEventTransceiver(window);
-      safariShim.shimGetUserMedia(window);
-
-      commonShim.shimRTCIceCandidate(window);
-      commonShim.shimMaxMessageSize(window);
-      commonShim.shimSendThrowTypeError(window);
-      break;
-    default:
-      logging('Unsupported browser!');
-      break;
-  }
-
-  return adapter;
-};
-
-},{"./chrome/chrome_shim":18,"./common_shim":20,"./edge/edge_shim":21,"./firefox/firefox_shim":24,"./safari/safari_shim":26,"./utils":27}],18:[function(require,module,exports){
-
-/*
- *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree.
- */
- /* eslint-env node */
-'use strict';
-var utils = require('../utils.js');
-var logging = utils.log;
-
-/* iterates the stats graph recursively. */
-function walkStats(stats, base, resultSet) {
-  if (!base || resultSet.has(base.id)) {
-    return;
-  }
-  resultSet.set(base.id, base);
-  Object.keys(base).forEach(function(name) {
-    if (name.endsWith('Id')) {
-      walkStats(stats, stats.get(base[name]), resultSet);
-    } else if (name.endsWith('Ids')) {
-      base[name].forEach(function(id) {
-        walkStats(stats, stats.get(id), resultSet);
-      });
-    }
-  });
-}
-
-/* filter getStats for a sender/receiver track. */
-function filterStats(result, track, outbound) {
-  var streamStatsType = outbound ? 'outbound-rtp' : 'inbound-rtp';
-  var filteredResult = new Map();
-  if (track === null) {
-    return filteredResult;
-  }
-  var trackStats = [];
-  result.forEach(function(value) {
-    if (value.type === 'track' &&
-        value.trackIdentifier === track.id) {
-      trackStats.push(value);
-    }
-  });
-  trackStats.forEach(function(trackStat) {
-    result.forEach(function(stats) {
-      if (stats.type === streamStatsType && stats.trackId === trackStat.id) {
-        walkStats(result, stats, filteredResult);
-      }
-    });
-  });
-  return filteredResult;
-}
-
-module.exports = {
-  shimGetUserMedia: require('./getusermedia'),
-  shimMediaStream: function(window) {
-    window.MediaStream = window.MediaStream || window.webkitMediaStream;
-  },
-
-  shimOnTrack: function(window) {
-    if (typeof window === 'object' && window.RTCPeerConnection && !('ontrack' in
-        window.RTCPeerConnection.prototype)) {
-      Object.defineProperty(window.RTCPeerConnection.prototype, 'ontrack', {
-        get: function() {
-          return this._ontrack;
-        },
-        set: function(f) {
-          if (this._ontrack) {
-            this.removeEventListener('track', this._ontrack);
-          }
-          this.addEventListener('track', this._ontrack = f);
-        },
-        enumerable: true,
-        configurable: true
-      });
-      var origSetRemoteDescription =
-          window.RTCPeerConnection.prototype.setRemoteDescription;
-      window.RTCPeerConnection.prototype.setRemoteDescription = function() {
-        var pc = this;
-        if (!pc._ontrackpoly) {
-          pc._ontrackpoly = function(e) {
-            // onaddstream does not fire when a track is added to an existing
-            // stream. But stream.onaddtrack is implemented so we use that.
-            e.stream.addEventListener('addtrack', function(te) {
-              var receiver;
-              if (window.RTCPeerConnection.prototype.getReceivers) {
-                receiver = pc.getReceivers().find(function(r) {
-                  return r.track && r.track.id === te.track.id;
-                });
-              } else {
-                receiver = {track: te.track};
-              }
-
-              var event = new Event('track');
-              event.track = te.track;
-              event.receiver = receiver;
-              event.transceiver = {receiver: receiver};
-              event.streams = [e.stream];
-              pc.dispatchEvent(event);
-            });
-            e.stream.getTracks().forEach(function(track) {
-              var receiver;
-              if (window.RTCPeerConnection.prototype.getReceivers) {
-                receiver = pc.getReceivers().find(function(r) {
-                  return r.track && r.track.id === track.id;
-                });
-              } else {
-                receiver = {track: track};
-              }
-              var event = new Event('track');
-              event.track = track;
-              event.receiver = receiver;
-              event.transceiver = {receiver: receiver};
-              event.streams = [e.stream];
-              pc.dispatchEvent(event);
-            });
-          };
-          pc.addEventListener('addstream', pc._ontrackpoly);
-        }
-        return origSetRemoteDescription.apply(pc, arguments);
-      };
-    } else if (!('RTCRtpTransceiver' in window)) {
-      utils.wrapPeerConnectionEvent(window, 'track', function(e) {
-        if (!e.transceiver) {
-          e.transceiver = {receiver: e.receiver};
-        }
-        return e;
-      });
-    }
-  },
-
-  shimGetSendersWithDtmf: function(window) {
-    // Overrides addTrack/removeTrack, depends on shimAddTrackRemoveTrack.
-    if (typeof window === 'object' && window.RTCPeerConnection &&
-        !('getSenders' in window.RTCPeerConnection.prototype) &&
-        'createDTMFSender' in window.RTCPeerConnection.prototype) {
-      var shimSenderWithDtmf = function(pc, track) {
-        return {
-          track: track,
-          get dtmf() {
-            if (this._dtmf === undefined) {
-              if (track.kind === 'audio') {
-                this._dtmf = pc.createDTMFSender(track);
-              } else {
-                this._dtmf = null;
-              }
-            }
-            return this._dtmf;
-          },
-          _pc: pc
-        };
-      };
-
-      // augment addTrack when getSenders is not available.
-      if (!window.RTCPeerConnection.prototype.getSenders) {
-        window.RTCPeerConnection.prototype.getSenders = function() {
-          this._senders = this._senders || [];
-          return this._senders.slice(); // return a copy of the internal state.
-        };
-        var origAddTrack = window.RTCPeerConnection.prototype.addTrack;
-        window.RTCPeerConnection.prototype.addTrack = function(track, stream) {
-          var pc = this;
-          var sender = origAddTrack.apply(pc, arguments);
-          if (!sender) {
-            sender = shimSenderWithDtmf(pc, track);
-            pc._senders.push(sender);
-          }
-          return sender;
-        };
-
-        var origRemoveTrack = window.RTCPeerConnection.prototype.removeTrack;
-        window.RTCPeerConnection.prototype.removeTrack = function(sender) {
-          var pc = this;
-          origRemoveTrack.apply(pc, arguments);
-          var idx = pc._senders.indexOf(sender);
-          if (idx !== -1) {
-            pc._senders.splice(idx, 1);
-          }
-        };
-      }
-      var origAddStream = window.RTCPeerConnection.prototype.addStream;
-      window.RTCPeerConnection.prototype.addStream = function(stream) {
-        var pc = this;
-        pc._senders = pc._senders || [];
-        origAddStream.apply(pc, [stream]);
-        stream.getTracks().forEach(function(track) {
-          pc._senders.push(shimSenderWithDtmf(pc, track));
-        });
-      };
-
-      var origRemoveStream = window.RTCPeerConnection.prototype.removeStream;
-      window.RTCPeerConnection.prototype.removeStream = function(stream) {
-        var pc = this;
-        pc._senders = pc._senders || [];
-        origRemoveStream.apply(pc, [stream]);
-
-        stream.getTracks().forEach(function(track) {
-          var sender = pc._senders.find(function(s) {
-            return s.track === track;
-          });
-          if (sender) {
-            pc._senders.splice(pc._senders.indexOf(sender), 1); // remove sender
-          }
-        });
-      };
-    } else if (typeof window === 'object' && window.RTCPeerConnection &&
-               'getSenders' in window.RTCPeerConnection.prototype &&
-               'createDTMFSender' in window.RTCPeerConnection.prototype &&
-               window.RTCRtpSender &&
-               !('dtmf' in window.RTCRtpSender.prototype)) {
-      var origGetSenders = window.RTCPeerConnection.prototype.getSenders;
-      window.RTCPeerConnection.prototype.getSenders = function() {
-        var pc = this;
-        var senders = origGetSenders.apply(pc, []);
-        senders.forEach(function(sender) {
-          sender._pc = pc;
-        });
-        return senders;
-      };
-
-      Object.defineProperty(window.RTCRtpSender.prototype, 'dtmf', {
-        get: function() {
-          if (this._dtmf === undefined) {
-            if (this.track.kind === 'audio') {
-              this._dtmf = this._pc.createDTMFSender(this.track);
-            } else {
-              this._dtmf = null;
-            }
-          }
-          return this._dtmf;
-        }
-      });
-    }
-  },
-
-  shimSenderReceiverGetStats: function(window) {
-    if (!(typeof window === 'object' && window.RTCPeerConnection &&
-        window.RTCRtpSender && window.RTCRtpReceiver)) {
-      return;
-    }
-
-    // shim sender stats.
-    if (!('getStats' in window.RTCRtpSender.prototype)) {
-      var origGetSenders = window.RTCPeerConnection.prototype.getSenders;
-      if (origGetSenders) {
-        window.RTCPeerConnection.prototype.getSenders = function() {
-          var pc = this;
-          var senders = origGetSenders.apply(pc, []);
-          senders.forEach(function(sender) {
-            sender._pc = pc;
-          });
-          return senders;
-        };
-      }
-
-      var origAddTrack = window.RTCPeerConnection.prototype.addTrack;
-      if (origAddTrack) {
-        window.RTCPeerConnection.prototype.addTrack = function() {
-          var sender = origAddTrack.apply(this, arguments);
-          sender._pc = this;
-          return sender;
-        };
-      }
-      window.RTCRtpSender.prototype.getStats = function() {
-        var sender = this;
-        return this._pc.getStats().then(function(result) {
-          /* Note: this will include stats of all senders that
-           *   send a track with the same id as sender.track as
-           *   it is not possible to identify the RTCRtpSender.
-           */
-          return filterStats(result, sender.track, true);
-        });
-      };
-    }
-
-    // shim receiver stats.
-    if (!('getStats' in window.RTCRtpReceiver.prototype)) {
-      var origGetReceivers = window.RTCPeerConnection.prototype.getReceivers;
-      if (origGetReceivers) {
-        window.RTCPeerConnection.prototype.getReceivers = function() {
-          var pc = this;
-          var receivers = origGetReceivers.apply(pc, []);
-          receivers.forEach(function(receiver) {
-            receiver._pc = pc;
-          });
-          return receivers;
-        };
-      }
-      utils.wrapPeerConnectionEvent(window, 'track', function(e) {
-        e.receiver._pc = e.srcElement;
-        return e;
-      });
-      window.RTCRtpReceiver.prototype.getStats = function() {
-        var receiver = this;
-        return this._pc.getStats().then(function(result) {
-          return filterStats(result, receiver.track, false);
-        });
-      };
-    }
-
-    if (!('getStats' in window.RTCRtpSender.prototype &&
-        'getStats' in window.RTCRtpReceiver.prototype)) {
-      return;
-    }
-
-    // shim RTCPeerConnection.getStats(track).
-    var origGetStats = window.RTCPeerConnection.prototype.getStats;
-    window.RTCPeerConnection.prototype.getStats = function() {
-      var pc = this;
-      if (arguments.length > 0 &&
-          arguments[0] instanceof window.MediaStreamTrack) {
-        var track = arguments[0];
-        var sender;
-        var receiver;
-        var err;
-        pc.getSenders().forEach(function(s) {
-          if (s.track === track) {
-            if (sender) {
-              err = true;
-            } else {
-              sender = s;
-            }
-          }
-        });
-        pc.getReceivers().forEach(function(r) {
-          if (r.track === track) {
-            if (receiver) {
-              err = true;
-            } else {
-              receiver = r;
-            }
-          }
-          return r.track === track;
-        });
-        if (err || (sender && receiver)) {
-          return Promise.reject(new DOMException(
-            'There are more than one sender or receiver for the track.',
-            'InvalidAccessError'));
-        } else if (sender) {
-          return sender.getStats();
-        } else if (receiver) {
-          return receiver.getStats();
-        }
-        return Promise.reject(new DOMException(
-          'There is no sender or receiver for the track.',
-          'InvalidAccessError'));
-      }
-      return origGetStats.apply(pc, arguments);
-    };
-  },
-
-  shimSourceObject: function(window) {
-    var URL = window && window.URL;
-
-    if (typeof window === 'object') {
-      if (window.HTMLMediaElement &&
-        !('srcObject' in window.HTMLMediaElement.prototype)) {
-        // Shim the srcObject property, once, when HTMLMediaElement is found.
-        Object.defineProperty(window.HTMLMediaElement.prototype, 'srcObject', {
-          get: function() {
-            return this._srcObject;
-          },
-          set: function(stream) {
-            var self = this;
-            // Use _srcObject as a private property for this shim
-            this._srcObject = stream;
-            if (this.src) {
-              URL.revokeObjectURL(this.src);
-            }
-
-            if (!stream) {
-              this.src = '';
-              return undefined;
-            }
-            this.src = URL.createObjectURL(stream);
-            // We need to recreate the blob url when a track is added or
-            // removed. Doing it manually since we want to avoid a recursion.
-            stream.addEventListener('addtrack', function() {
-              if (self.src) {
-                URL.revokeObjectURL(self.src);
-              }
-              self.src = URL.createObjectURL(stream);
-            });
-            stream.addEventListener('removetrack', function() {
-              if (self.src) {
-                URL.revokeObjectURL(self.src);
-              }
-              self.src = URL.createObjectURL(stream);
-            });
-          }
-        });
-      }
-    }
-  },
-
-  shimAddTrackRemoveTrackWithNative: function(window) {
-    // shim addTrack/removeTrack with native variants in order to make
-    // the interactions with legacy getLocalStreams behave as in other browsers.
-    // Keeps a mapping stream.id => [stream, rtpsenders...]
-    window.RTCPeerConnection.prototype.getLocalStreams = function() {
-      var pc = this;
-      this._shimmedLocalStreams = this._shimmedLocalStreams || {};
-      return Object.keys(this._shimmedLocalStreams).map(function(streamId) {
-        return pc._shimmedLocalStreams[streamId][0];
-      });
-    };
-
-    var origAddTrack = window.RTCPeerConnection.prototype.addTrack;
-    window.RTCPeerConnection.prototype.addTrack = function(track, stream) {
-      if (!stream) {
-        return origAddTrack.apply(this, arguments);
-      }
-      this._shimmedLocalStreams = this._shimmedLocalStreams || {};
-
-      var sender = origAddTrack.apply(this, arguments);
-      if (!this._shimmedLocalStreams[stream.id]) {
-        this._shimmedLocalStreams[stream.id] = [stream, sender];
-      } else if (this._shimmedLocalStreams[stream.id].indexOf(sender) === -1) {
-        this._shimmedLocalStreams[stream.id].push(sender);
-      }
-      return sender;
-    };
-
-    var origAddStream = window.RTCPeerConnection.prototype.addStream;
-    window.RTCPeerConnection.prototype.addStream = function(stream) {
-      var pc = this;
-      this._shimmedLocalStreams = this._shimmedLocalStreams || {};
-
-      stream.getTracks().forEach(function(track) {
-        var alreadyExists = pc.getSenders().find(function(s) {
-          return s.track === track;
-        });
-        if (alreadyExists) {
-          throw new DOMException('Track already exists.',
-              'InvalidAccessError');
-        }
-      });
-      var existingSenders = pc.getSenders();
-      origAddStream.apply(this, arguments);
-      var newSenders = pc.getSenders().filter(function(newSender) {
-        return existingSenders.indexOf(newSender) === -1;
-      });
-      this._shimmedLocalStreams[stream.id] = [stream].concat(newSenders);
-    };
-
-    var origRemoveStream = window.RTCPeerConnection.prototype.removeStream;
-    window.RTCPeerConnection.prototype.removeStream = function(stream) {
-      this._shimmedLocalStreams = this._shimmedLocalStreams || {};
-      delete this._shimmedLocalStreams[stream.id];
-      return origRemoveStream.apply(this, arguments);
-    };
-
-    var origRemoveTrack = window.RTCPeerConnection.prototype.removeTrack;
-    window.RTCPeerConnection.prototype.removeTrack = function(sender) {
-      var pc = this;
-      this._shimmedLocalStreams = this._shimmedLocalStreams || {};
-      if (sender) {
-        Object.keys(this._shimmedLocalStreams).forEach(function(streamId) {
-          var idx = pc._shimmedLocalStreams[streamId].indexOf(sender);
-          if (idx !== -1) {
-            pc._shimmedLocalStreams[streamId].splice(idx, 1);
-          }
-          if (pc._shimmedLocalStreams[streamId].length === 1) {
-            delete pc._shimmedLocalStreams[streamId];
-          }
-        });
-      }
-      return origRemoveTrack.apply(this, arguments);
-    };
-  },
-
-  shimAddTrackRemoveTrack: function(window) {
-    var browserDetails = utils.detectBrowser(window);
-    // shim addTrack and removeTrack.
-    if (window.RTCPeerConnection.prototype.addTrack &&
-        browserDetails.version >= 65) {
-      return this.shimAddTrackRemoveTrackWithNative(window);
-    }
-
-    // also shim pc.getLocalStreams when addTrack is shimmed
-    // to return the original streams.
-    var origGetLocalStreams = window.RTCPeerConnection.prototype
-        .getLocalStreams;
-    window.RTCPeerConnection.prototype.getLocalStreams = function() {
-      var pc = this;
-      var nativeStreams = origGetLocalStreams.apply(this);
-      pc._reverseStreams = pc._reverseStreams || {};
-      return nativeStreams.map(function(stream) {
-        return pc._reverseStreams[stream.id];
-      });
-    };
-
-    var origAddStream = window.RTCPeerConnection.prototype.addStream;
-    window.RTCPeerConnection.prototype.addStream = function(stream) {
-      var pc = this;
-      pc._streams = pc._streams || {};
-      pc._reverseStreams = pc._reverseStreams || {};
-
-      stream.getTracks().forEach(function(track) {
-        var alreadyExists = pc.getSenders().find(function(s) {
-          return s.track === track;
-        });
-        if (alreadyExists) {
-          throw new DOMException('Track already exists.',
-              'InvalidAccessError');
-        }
-      });
-      // Add identity mapping for consistency with addTrack.
-      // Unless this is being used with a stream from addTrack.
-      if (!pc._reverseStreams[stream.id]) {
-        var newStream = new window.MediaStream(stream.getTracks());
-        pc._streams[stream.id] = newStream;
-        pc._reverseStreams[newStream.id] = stream;
-        stream = newStream;
-      }
-      origAddStream.apply(pc, [stream]);
-    };
-
-    var origRemoveStream = window.RTCPeerConnection.prototype.removeStream;
-    window.RTCPeerConnection.prototype.removeStream = function(stream) {
-      var pc = this;
-      pc._streams = pc._streams || {};
-      pc._reverseStreams = pc._reverseStreams || {};
-
-      origRemoveStream.apply(pc, [(pc._streams[stream.id] || stream)]);
-      delete pc._reverseStreams[(pc._streams[stream.id] ?
-          pc._streams[stream.id].id : stream.id)];
-      delete pc._streams[stream.id];
-    };
-
-    window.RTCPeerConnection.prototype.addTrack = function(track, stream) {
-      var pc = this;
-      if (pc.signalingState === 'closed') {
-        throw new DOMException(
-          'The RTCPeerConnection\'s signalingState is \'closed\'.',
-          'InvalidStateError');
-      }
-      var streams = [].slice.call(arguments, 1);
-      if (streams.length !== 1 ||
-          !streams[0].getTracks().find(function(t) {
-            return t === track;
-          })) {
-        // this is not fully correct but all we can manage without
-        // [[associated MediaStreams]] internal slot.
-        throw new DOMException(
-          'The adapter.js addTrack polyfill only supports a single ' +
-          ' stream which is associated with the specified track.',
-          'NotSupportedError');
-      }
-
-      var alreadyExists = pc.getSenders().find(function(s) {
-        return s.track === track;
-      });
-      if (alreadyExists) {
-        throw new DOMException('Track already exists.',
-            'InvalidAccessError');
-      }
-
-      pc._streams = pc._streams || {};
-      pc._reverseStreams = pc._reverseStreams || {};
-      var oldStream = pc._streams[stream.id];
-      if (oldStream) {
-        // this is using odd Chrome behaviour, use with caution:
-        // https://bugs.chromium.org/p/webrtc/issues/detail?id=7815
-        // Note: we rely on the high-level addTrack/dtmf shim to
-        // create the sender with a dtmf sender.
-        oldStream.addTrack(track);
-
-        // Trigger ONN async.
-        Promise.resolve().then(function() {
-          pc.dispatchEvent(new Event('negotiationneeded'));
-        });
-      } else {
-        var newStream = new window.MediaStream([track]);
-        pc._streams[stream.id] = newStream;
-        pc._reverseStreams[newStream.id] = stream;
-        pc.addStream(newStream);
-      }
-      return pc.getSenders().find(function(s) {
-        return s.track === track;
-      });
-    };
-
-    // replace the internal stream id with the external one and
-    // vice versa.
-    function replaceInternalStreamId(pc, description) {
-      var sdp = description.sdp;
-      Object.keys(pc._reverseStreams || []).forEach(function(internalId) {
-        var externalStream = pc._reverseStreams[internalId];
-        var internalStream = pc._streams[externalStream.id];
-        sdp = sdp.replace(new RegExp(internalStream.id, 'g'),
-            externalStream.id);
-      });
-      return new RTCSessionDescription({
-        type: description.type,
-        sdp: sdp
-      });
-    }
-    function replaceExternalStreamId(pc, description) {
-      var sdp = description.sdp;
-      Object.keys(pc._reverseStreams || []).forEach(function(internalId) {
-        var externalStream = pc._reverseStreams[internalId];
-        var internalStream = pc._streams[externalStream.id];
-        sdp = sdp.replace(new RegExp(externalStream.id, 'g'),
-            internalStream.id);
-      });
-      return new RTCSessionDescription({
-        type: description.type,
-        sdp: sdp
-      });
-    }
-    ['createOffer', 'createAnswer'].forEach(function(method) {
-      var nativeMethod = window.RTCPeerConnection.prototype[method];
-      window.RTCPeerConnection.prototype[method] = function() {
-        var pc = this;
-        var args = arguments;
-        var isLegacyCall = arguments.length &&
-            typeof arguments[0] === 'function';
-        if (isLegacyCall) {
-          return nativeMethod.apply(pc, [
-            function(description) {
-              var desc = replaceInternalStreamId(pc, description);
-              args[0].apply(null, [desc]);
-            },
-            function(err) {
-              if (args[1]) {
-                args[1].apply(null, err);
-              }
-            }, arguments[2]
-          ]);
-        }
-        return nativeMethod.apply(pc, arguments)
-        .then(function(description) {
-          return replaceInternalStreamId(pc, description);
-        });
-      };
-    });
-
-    var origSetLocalDescription =
-        window.RTCPeerConnection.prototype.setLocalDescription;
-    window.RTCPeerConnection.prototype.setLocalDescription = function() {
-      var pc = this;
-      if (!arguments.length || !arguments[0].type) {
-        return origSetLocalDescription.apply(pc, arguments);
-      }
-      arguments[0] = replaceExternalStreamId(pc, arguments[0]);
-      return origSetLocalDescription.apply(pc, arguments);
-    };
-
-    // TODO: mangle getStats: https://w3c.github.io/webrtc-stats/#dom-rtcmediastreamstats-streamidentifier
-
-    var origLocalDescription = Object.getOwnPropertyDescriptor(
-        window.RTCPeerConnection.prototype, 'localDescription');
-    Object.defineProperty(window.RTCPeerConnection.prototype,
-        'localDescription', {
-          get: function() {
-            var pc = this;
-            var description = origLocalDescription.get.apply(this);
-            if (description.type === '') {
-              return description;
-            }
-            return replaceInternalStreamId(pc, description);
-          }
-        });
-
-    window.RTCPeerConnection.prototype.removeTrack = function(sender) {
-      var pc = this;
-      if (pc.signalingState === 'closed') {
-        throw new DOMException(
-          'The RTCPeerConnection\'s signalingState is \'closed\'.',
-          'InvalidStateError');
-      }
-      // We can not yet check for sender instanceof RTCRtpSender
-      // since we shim RTPSender. So we check if sender._pc is set.
-      if (!sender._pc) {
-        throw new DOMException('Argument 1 of RTCPeerConnection.removeTrack ' +
-            'does not implement interface RTCRtpSender.', 'TypeError');
-      }
-      var isLocal = sender._pc === pc;
-      if (!isLocal) {
-        throw new DOMException('Sender was not created by this connection.',
-            'InvalidAccessError');
-      }
-
-      // Search for the native stream the senders track belongs to.
-      pc._streams = pc._streams || {};
-      var stream;
-      Object.keys(pc._streams).forEach(function(streamid) {
-        var hasTrack = pc._streams[streamid].getTracks().find(function(track) {
-          return sender.track === track;
-        });
-        if (hasTrack) {
-          stream = pc._streams[streamid];
-        }
-      });
-
-      if (stream) {
-        if (stream.getTracks().length === 1) {
-          // if this is the last track of the stream, remove the stream. This
-          // takes care of any shimmed _senders.
-          pc.removeStream(pc._reverseStreams[stream.id]);
-        } else {
-          // relying on the same odd chrome behaviour as above.
-          stream.removeTrack(sender.track);
-        }
-        pc.dispatchEvent(new Event('negotiationneeded'));
-      }
-    };
-  },
-
-  shimPeerConnection: function(window) {
-    var browserDetails = utils.detectBrowser(window);
-
-    // The RTCPeerConnection object.
-    if (!window.RTCPeerConnection && window.webkitRTCPeerConnection) {
-      window.RTCPeerConnection = function(pcConfig, pcConstraints) {
-        // Translate iceTransportPolicy to iceTransports,
-        // see https://code.google.com/p/webrtc/issues/detail?id=4869
-        // this was fixed in M56 along with unprefixing RTCPeerConnection.
-        logging('PeerConnection');
-        if (pcConfig && pcConfig.iceTransportPolicy) {
-          pcConfig.iceTransports = pcConfig.iceTransportPolicy;
-        }
-
-        return new window.webkitRTCPeerConnection(pcConfig, pcConstraints);
-      };
-      window.RTCPeerConnection.prototype =
-          window.webkitRTCPeerConnection.prototype;
-      // wrap static methods. Currently just generateCertificate.
-      if (window.webkitRTCPeerConnection.generateCertificate) {
-        Object.defineProperty(window.RTCPeerConnection, 'generateCertificate', {
-          get: function() {
-            return window.webkitRTCPeerConnection.generateCertificate;
-          }
-        });
-      }
-    } else {
-      // migrate from non-spec RTCIceServer.url to RTCIceServer.urls
-      var OrigPeerConnection = window.RTCPeerConnection;
-      window.RTCPeerConnection = function(pcConfig, pcConstraints) {
-        if (pcConfig && pcConfig.iceServers) {
-          var newIceServers = [];
-          for (var i = 0; i < pcConfig.iceServers.length; i++) {
-            var server = pcConfig.iceServers[i];
-            if (!server.hasOwnProperty('urls') &&
-                server.hasOwnProperty('url')) {
-              utils.deprecated('RTCIceServer.url', 'RTCIceServer.urls');
-              server = JSON.parse(JSON.stringify(server));
-              server.urls = server.url;
-              newIceServers.push(server);
-            } else {
-              newIceServers.push(pcConfig.iceServers[i]);
-            }
-          }
-          pcConfig.iceServers = newIceServers;
-        }
-        return new OrigPeerConnection(pcConfig, pcConstraints);
-      };
-      window.RTCPeerConnection.prototype = OrigPeerConnection.prototype;
-      // wrap static methods. Currently just generateCertificate.
-      Object.defineProperty(window.RTCPeerConnection, 'generateCertificate', {
-        get: function() {
-          return OrigPeerConnection.generateCertificate;
-        }
-      });
-    }
-
-    var origGetStats = window.RTCPeerConnection.prototype.getStats;
-    window.RTCPeerConnection.prototype.getStats = function(selector,
-        successCallback, errorCallback) {
-      var pc = this;
-      var args = arguments;
-
-      // If selector is a function then we are in the old style stats so just
-      // pass back the original getStats format to avoid breaking old users.
-      if (arguments.length > 0 && typeof selector === 'function') {
-        return origGetStats.apply(this, arguments);
-      }
-
-      // When spec-style getStats is supported, return those when called with
-      // either no arguments or the selector argument is null.
-      if (origGetStats.length === 0 && (arguments.length === 0 ||
-          typeof arguments[0] !== 'function')) {
-        return origGetStats.apply(this, []);
-      }
-
-      var fixChromeStats_ = function(response) {
-        var standardReport = {};
-        var reports = response.result();
-        reports.forEach(function(report) {
-          var standardStats = {
-            id: report.id,
-            timestamp: report.timestamp,
-            type: {
-              localcandidate: 'local-candidate',
-              remotecandidate: 'remote-candidate'
-            }[report.type] || report.type
-          };
-          report.names().forEach(function(name) {
-            standardStats[name] = report.stat(name);
-          });
-          standardReport[standardStats.id] = standardStats;
-        });
-
-        return standardReport;
-      };
-
-      // shim getStats with maplike support
-      var makeMapStats = function(stats) {
-        return new Map(Object.keys(stats).map(function(key) {
-          return [key, stats[key]];
-        }));
-      };
-
-      if (arguments.length >= 2) {
-        var successCallbackWrapper_ = function(response) {
-          args[1](makeMapStats(fixChromeStats_(response)));
-        };
-
-        return origGetStats.apply(this, [successCallbackWrapper_,
-          arguments[0]]);
-      }
-
-      // promise-support
-      return new Promise(function(resolve, reject) {
-        origGetStats.apply(pc, [
-          function(response) {
-            resolve(makeMapStats(fixChromeStats_(response)));
-          }, reject]);
-      }).then(successCallback, errorCallback);
-    };
-
-    // add promise support -- natively available in Chrome 51
-    if (browserDetails.version < 51) {
-      ['setLocalDescription', 'setRemoteDescription', 'addIceCandidate']
-          .forEach(function(method) {
-            var nativeMethod = window.RTCPeerConnection.prototype[method];
-            window.RTCPeerConnection.prototype[method] = function() {
-              var args = arguments;
-              var pc = this;
-              var promise = new Promise(function(resolve, reject) {
-                nativeMethod.apply(pc, [args[0], resolve, reject]);
-              });
-              if (args.length < 2) {
-                return promise;
-              }
-              return promise.then(function() {
-                args[1].apply(null, []);
-              },
-              function(err) {
-                if (args.length >= 3) {
-                  args[2].apply(null, [err]);
-                }
-              });
-            };
-          });
-    }
-
-    // promise support for createOffer and createAnswer. Available (without
-    // bugs) since M52: crbug/619289
-    if (browserDetails.version < 52) {
-      ['createOffer', 'createAnswer'].forEach(function(method) {
-        var nativeMethod = window.RTCPeerConnection.prototype[method];
-        window.RTCPeerConnection.prototype[method] = function() {
-          var pc = this;
-          if (arguments.length < 1 || (arguments.length === 1 &&
-              typeof arguments[0] === 'object')) {
-            var opts = arguments.length === 1 ? arguments[0] : undefined;
-            return new Promise(function(resolve, reject) {
-              nativeMethod.apply(pc, [resolve, reject, opts]);
-            });
-          }
-          return nativeMethod.apply(this, arguments);
-        };
-      });
-    }
-
-    // shim implicit creation of RTCSessionDescription/RTCIceCandidate
-    ['setLocalDescription', 'setRemoteDescription', 'addIceCandidate']
-        .forEach(function(method) {
-          var nativeMethod = window.RTCPeerConnection.prototype[method];
-          window.RTCPeerConnection.prototype[method] = function() {
-            arguments[0] = new ((method === 'addIceCandidate') ?
-                window.RTCIceCandidate :
-                window.RTCSessionDescription)(arguments[0]);
-            return nativeMethod.apply(this, arguments);
-          };
-        });
-
-    // support for addIceCandidate(null or undefined)
-    var nativeAddIceCandidate =
-        window.RTCPeerConnection.prototype.addIceCandidate;
-    window.RTCPeerConnection.prototype.addIceCandidate = function() {
-      if (!arguments[0]) {
-        if (arguments[1]) {
-          arguments[1].apply(null);
-        }
-        return Promise.resolve();
-      }
-      return nativeAddIceCandidate.apply(this, arguments);
-    };
-  },
-
-  fixNegotiationNeeded: function(window) {
-    utils.wrapPeerConnectionEvent(window, 'negotiationneeded', function(e) {
-      var pc = e.target;
-      if (pc.signalingState !== 'stable') {
-        return;
-      }
-      return e;
-    });
-  },
-
-  shimGetDisplayMedia: function(window, getSourceId) {
-    if ('getDisplayMedia' in window.navigator) {
-      return;
-    }
-    // getSourceId is a function that returns a promise resolving with
-    // the sourceId of the screen/window/tab to be shared.
-    if (typeof getSourceId !== 'function') {
-      console.error('shimGetDisplayMedia: getSourceId argument is not ' +
-          'a function');
-      return;
-    }
-    navigator.getDisplayMedia = function(constraints) {
-      return getSourceId(constraints)
-        .then(function(sourceId) {
-          constraints.video = {
-            mandatory: {
-              chromeMediaSource: 'desktop',
-              chromeMediaSourceId: sourceId,
-              maxFrameRate: constraints.video.frameRate || 3
-            }
-          };
-          return navigator.mediaDevices.getUserMedia(constraints);
-        });
-    };
-  }
-};
-
-},{"../utils.js":27,"./getusermedia":19}],19:[function(require,module,exports){
-/*
- *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree.
- */
- /* eslint-env node */
-'use strict';
-var utils = require('../utils.js');
-var logging = utils.log;
-
-// Expose public methods.
-module.exports = function(window) {
-  var browserDetails = utils.detectBrowser(window);
-  var navigator = window && window.navigator;
-
-  var constraintsToChrome_ = function(c) {
-    if (typeof c !== 'object' || c.mandatory || c.optional) {
-      return c;
-    }
-    var cc = {};
-    Object.keys(c).forEach(function(key) {
-      if (key === 'require' || key === 'advanced' || key === 'mediaSource') {
-        return;
-      }
-      var r = (typeof c[key] === 'object') ? c[key] : {ideal: c[key]};
-      if (r.exact !== undefined && typeof r.exact === 'number') {
-        r.min = r.max = r.exact;
-      }
-      var oldname_ = function(prefix, name) {
-        if (prefix) {
-          return prefix + name.charAt(0).toUpperCase() + name.slice(1);
-        }
-        return (name === 'deviceId') ? 'sourceId' : name;
-      };
-      if (r.ideal !== undefined) {
-        cc.optional = cc.optional || [];
-        var oc = {};
-        if (typeof r.ideal === 'number') {
-          oc[oldname_('min', key)] = r.ideal;
-          cc.optional.push(oc);
-          oc = {};
-          oc[oldname_('max', key)] = r.ideal;
-          cc.optional.push(oc);
-        } else {
-          oc[oldname_('', key)] = r.ideal;
-          cc.optional.push(oc);
-        }
-      }
-      if (r.exact !== undefined && typeof r.exact !== 'number') {
-        cc.mandatory = cc.mandatory || {};
-        cc.mandatory[oldname_('', key)] = r.exact;
-      } else {
-        ['min', 'max'].forEach(function(mix) {
-          if (r[mix] !== undefined) {
-            cc.mandatory = cc.mandatory || {};
-            cc.mandatory[oldname_(mix, key)] = r[mix];
-          }
-        });
-      }
-    });
-    if (c.advanced) {
-      cc.optional = (cc.optional || []).concat(c.advanced);
-    }
-    return cc;
-  };
-
-  var shimConstraints_ = function(constraints, func) {
-    if (browserDetails.version >= 61) {
-      return func(constraints);
-    }
-    constraints = JSON.parse(JSON.stringify(constraints));
-    if (constraints && typeof constraints.audio === 'object') {
-      var remap = function(obj, a, b) {
-        if (a in obj && !(b in obj)) {
-          obj[b] = obj[a];
-          delete obj[a];
-        }
-      };
-      constraints = JSON.parse(JSON.stringify(constraints));
-      remap(constraints.audio, 'autoGainControl', 'googAutoGainControl');
-      remap(constraints.audio, 'noiseSuppression', 'googNoiseSuppression');
-      constraints.audio = constraintsToChrome_(constraints.audio);
-    }
-    if (constraints && typeof constraints.video === 'object') {
-      // Shim facingMode for mobile & surface pro.
-      var face = constraints.video.facingMode;
-      face = face && ((typeof face === 'object') ? face : {ideal: face});
-      var getSupportedFacingModeLies = browserDetails.version < 66;
-
-      if ((face && (face.exact === 'user' || face.exact === 'environment' ||
-                    face.ideal === 'user' || face.ideal === 'environment')) &&
-          !(navigator.mediaDevices.getSupportedConstraints &&
-            navigator.mediaDevices.getSupportedConstraints().facingMode &&
-            !getSupportedFacingModeLies)) {
-        delete constraints.video.facingMode;
-        var matches;
-        if (face.exact === 'environment' || face.ideal === 'environment') {
-          matches = ['back', 'rear'];
-        } else if (face.exact === 'user' || face.ideal === 'user') {
-          matches = ['front'];
-        }
-        if (matches) {
-          // Look for matches in label, or use last cam for back (typical).
-          return navigator.mediaDevices.enumerateDevices()
-          .then(function(devices) {
-            devices = devices.filter(function(d) {
-              return d.kind === 'videoinput';
-            });
-            var dev = devices.find(function(d) {
-              return matches.some(function(match) {
-                return d.label.toLowerCase().indexOf(match) !== -1;
-              });
-            });
-            if (!dev && devices.length && matches.indexOf('back') !== -1) {
-              dev = devices[devices.length - 1]; // more likely the back cam
-            }
-            if (dev) {
-              constraints.video.deviceId = face.exact ? {exact: dev.deviceId} :
-                                                        {ideal: dev.deviceId};
-            }
-            constraints.video = constraintsToChrome_(constraints.video);
-            logging('chrome: ' + JSON.stringify(constraints));
-            return func(constraints);
-          });
-        }
-      }
-      constraints.video = constraintsToChrome_(constraints.video);
-    }
-    logging('chrome: ' + JSON.stringify(constraints));
-    return func(constraints);
-  };
-
-  var shimError_ = function(e) {
-    if (browserDetails.version >= 64) {
-      return e;
-    }
-    return {
-      name: {
-        PermissionDeniedError: 'NotAllowedError',
-        PermissionDismissedError: 'NotAllowedError',
-        InvalidStateError: 'NotAllowedError',
-        DevicesNotFoundError: 'NotFoundError',
-        ConstraintNotSatisfiedError: 'OverconstrainedError',
-        TrackStartError: 'NotReadableError',
-        MediaDeviceFailedDueToShutdown: 'NotAllowedError',
-        MediaDeviceKillSwitchOn: 'NotAllowedError',
-        TabCaptureError: 'AbortError',
-        ScreenCaptureError: 'AbortError',
-        DeviceCaptureError: 'AbortError'
-      }[e.name] || e.name,
-      message: e.message,
-      constraint: e.constraint || e.constraintName,
-      toString: function() {
-        return this.name + (this.message && ': ') + this.message;
-      }
-    };
-  };
-
-  var getUserMedia_ = function(constraints, onSuccess, onError) {
-    shimConstraints_(constraints, function(c) {
-      navigator.webkitGetUserMedia(c, onSuccess, function(e) {
-        if (onError) {
-          onError(shimError_(e));
-        }
-      });
-    });
-  };
-
-  navigator.getUserMedia = getUserMedia_;
-
-  // Returns the result of getUserMedia as a Promise.
-  var getUserMediaPromise_ = function(constraints) {
-    return new Promise(function(resolve, reject) {
-      navigator.getUserMedia(constraints, resolve, reject);
-    });
-  };
-
-  if (!navigator.mediaDevices) {
-    navigator.mediaDevices = {
-      getUserMedia: getUserMediaPromise_,
-      enumerateDevices: function() {
-        return new Promise(function(resolve) {
-          var kinds = {audio: 'audioinput', video: 'videoinput'};
-          return window.MediaStreamTrack.getSources(function(devices) {
-            resolve(devices.map(function(device) {
-              return {label: device.label,
-                kind: kinds[device.kind],
-                deviceId: device.id,
-                groupId: ''};
-            }));
-          });
-        });
-      },
-      getSupportedConstraints: function() {
-        return {
-          deviceId: true, echoCancellation: true, facingMode: true,
-          frameRate: true, height: true, width: true
-        };
-      }
-    };
-  }
-
-  // A shim for getUserMedia method on the mediaDevices object.
-  // TODO(KaptenJansson) remove once implemented in Chrome stable.
-  if (!navigator.mediaDevices.getUserMedia) {
-    navigator.mediaDevices.getUserMedia = function(constraints) {
-      return getUserMediaPromise_(constraints);
-    };
-  } else {
-    // Even though Chrome 45 has navigator.mediaDevices and a getUserMedia
-    // function which returns a Promise, it does not accept spec-style
-    // constraints.
-    var origGetUserMedia = navigator.mediaDevices.getUserMedia.
-        bind(navigator.mediaDevices);
-    navigator.mediaDevices.getUserMedia = function(cs) {
-      return shimConstraints_(cs, function(c) {
-        return origGetUserMedia(c).then(function(stream) {
-          if (c.audio && !stream.getAudioTracks().length ||
-              c.video && !stream.getVideoTracks().length) {
-            stream.getTracks().forEach(function(track) {
-              track.stop();
-            });
-            throw new DOMException('', 'NotFoundError');
-          }
-          return stream;
-        }, function(e) {
-          return Promise.reject(shimError_(e));
-        });
-      });
-    };
-  }
-
-  // Dummy devicechange event methods.
-  // TODO(KaptenJansson) remove once implemented in Chrome stable.
-  if (typeof navigator.mediaDevices.addEventListener === 'undefined') {
-    navigator.mediaDevices.addEventListener = function() {
-      logging('Dummy mediaDevices.addEventListener called.');
-    };
-  }
-  if (typeof navigator.mediaDevices.removeEventListener === 'undefined') {
-    navigator.mediaDevices.removeEventListener = function() {
-      logging('Dummy mediaDevices.removeEventListener called.');
-    };
-  }
-};
-
-},{"../utils.js":27}],20:[function(require,module,exports){
-/*
- *  Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree.
- */
- /* eslint-env node */
-'use strict';
-
-var SDPUtils = require('sdp');
-var utils = require('./utils');
-
-module.exports = {
-  shimRTCIceCandidate: function(window) {
-    // foundation is arbitrarily chosen as an indicator for full support for
-    // https://w3c.github.io/webrtc-pc/#rtcicecandidate-interface
-    if (!window.RTCIceCandidate || (window.RTCIceCandidate && 'foundation' in
-        window.RTCIceCandidate.prototype)) {
-      return;
-    }
-
-    var NativeRTCIceCandidate = window.RTCIceCandidate;
-    window.RTCIceCandidate = function(args) {
-      // Remove the a= which shouldn't be part of the candidate string.
-      if (typeof args === 'object' && args.candidate &&
-          args.candidate.indexOf('a=') === 0) {
-        args = JSON.parse(JSON.stringify(args));
-        args.candidate = args.candidate.substr(2);
-      }
-
-      if (args.candidate && args.candidate.length) {
-        // Augment the native candidate with the parsed fields.
-        var nativeCandidate = new NativeRTCIceCandidate(args);
-        var parsedCandidate = SDPUtils.parseCandidate(args.candidate);
-        var augmentedCandidate = Object.assign(nativeCandidate,
-            parsedCandidate);
-
-        // Add a serializer that does not serialize the extra attributes.
-        augmentedCandidate.toJSON = function() {
-          return {
-            candidate: augmentedCandidate.candidate,
-            sdpMid: augmentedCandidate.sdpMid,
-            sdpMLineIndex: augmentedCandidate.sdpMLineIndex,
-            usernameFragment: augmentedCandidate.usernameFragment,
-          };
-        };
-        return augmentedCandidate;
-      }
-      return new NativeRTCIceCandidate(args);
-    };
-    window.RTCIceCandidate.prototype = NativeRTCIceCandidate.prototype;
-
-    // Hook up the augmented candidate in onicecandidate and
-    // addEventListener('icecandidate', ...)
-    utils.wrapPeerConnectionEvent(window, 'icecandidate', function(e) {
-      if (e.candidate) {
-        Object.defineProperty(e, 'candidate', {
-          value: new window.RTCIceCandidate(e.candidate),
-          writable: 'false'
-        });
-      }
-      return e;
-    });
-  },
-
-  // shimCreateObjectURL must be called before shimSourceObject to avoid loop.
-
-  shimCreateObjectURL: function(window) {
-    var URL = window && window.URL;
-
-    if (!(typeof window === 'object' && window.HTMLMediaElement &&
-          'srcObject' in window.HTMLMediaElement.prototype &&
-        URL.createObjectURL && URL.revokeObjectURL)) {
-      // Only shim CreateObjectURL using srcObject if srcObject exists.
-      return undefined;
-    }
-
-    var nativeCreateObjectURL = URL.createObjectURL.bind(URL);
-    var nativeRevokeObjectURL = URL.revokeObjectURL.bind(URL);
-    var streams = new Map(), newId = 0;
-
-    URL.createObjectURL = function(stream) {
-      if ('getTracks' in stream) {
-        var url = 'polyblob:' + (++newId);
-        streams.set(url, stream);
-        utils.deprecated('URL.createObjectURL(stream)',
-            'elem.srcObject = stream');
-        return url;
-      }
-      return nativeCreateObjectURL(stream);
-    };
-    URL.revokeObjectURL = function(url) {
-      nativeRevokeObjectURL(url);
-      streams.delete(url);
-    };
-
-    var dsc = Object.getOwnPropertyDescriptor(window.HTMLMediaElement.prototype,
-                                              'src');
-    Object.defineProperty(window.HTMLMediaElement.prototype, 'src', {
-      get: function() {
-        return dsc.get.apply(this);
-      },
-      set: function(url) {
-        this.srcObject = streams.get(url) || null;
-        return dsc.set.apply(this, [url]);
-      }
-    });
-
-    var nativeSetAttribute = window.HTMLMediaElement.prototype.setAttribute;
-    window.HTMLMediaElement.prototype.setAttribute = function() {
-      if (arguments.length === 2 &&
-          ('' + arguments[0]).toLowerCase() === 'src') {
-        this.srcObject = streams.get(arguments[1]) || null;
-      }
-      return nativeSetAttribute.apply(this, arguments);
-    };
-  },
-
-  shimMaxMessageSize: function(window) {
-    if (window.RTCSctpTransport || !window.RTCPeerConnection) {
-      return;
-    }
-    var browserDetails = utils.detectBrowser(window);
-
-    if (!('sctp' in window.RTCPeerConnection.prototype)) {
-      Object.defineProperty(window.RTCPeerConnection.prototype, 'sctp', {
-        get: function() {
-          return typeof this._sctp === 'undefined' ? null : this._sctp;
-        }
-      });
-    }
-
-    var sctpInDescription = function(description) {
-      var sections = SDPUtils.splitSections(description.sdp);
-      sections.shift();
-      return sections.some(function(mediaSection) {
-        var mLine = SDPUtils.parseMLine(mediaSection);
-        return mLine && mLine.kind === 'application'
-            && mLine.protocol.indexOf('SCTP') !== -1;
-      });
-    };
-
-    var getRemoteFirefoxVersion = function(description) {
-      // TODO: Is there a better solution for detecting Firefox?
-      var match = description.sdp.match(/mozilla...THIS_IS_SDPARTA-(\d+)/);
-      if (match === null || match.length < 2) {
-        return -1;
-      }
-      var version = parseInt(match[1], 10);
-      // Test for NaN (yes, this is ugly)
-      return version !== version ? -1 : version;
-    };
-
-    var getCanSendMaxMessageSize = function(remoteIsFirefox) {
-      // Every implementation we know can send at least 64 KiB.
-      // Note: Although Chrome is technically able to send up to 256 KiB, the
-      //       data does not reach the other peer reliably.
-      //       See: https://bugs.chromium.org/p/webrtc/issues/detail?id=8419
-      var canSendMaxMessageSize = 65536;
-      if (browserDetails.browser === 'firefox') {
-        if (browserDetails.version < 57) {
-          if (remoteIsFirefox === -1) {
-            // FF < 57 will send in 16 KiB chunks using the deprecated PPID
-            // fragmentation.
-            canSendMaxMessageSize = 16384;
-          } else {
-            // However, other FF (and RAWRTC) can reassemble PPID-fragmented
-            // messages. Thus, supporting ~2 GiB when sending.
-            canSendMaxMessageSize = 2147483637;
-          }
-        } else if (browserDetails.version < 60) {
-          // Currently, all FF >= 57 will reset the remote maximum message size
-          // to the default value when a data channel is created at a later
-          // stage. :(
-          // See: https://bugzilla.mozilla.org/show_bug.cgi?id=1426831
-          canSendMaxMessageSize =
-            browserDetails.version === 57 ? 65535 : 65536;
-        } else {
-          // FF >= 60 supports sending ~2 GiB
-          canSendMaxMessageSize = 2147483637;
-        }
-      }
-      return canSendMaxMessageSize;
-    };
-
-    var getMaxMessageSize = function(description, remoteIsFirefox) {
-      // Note: 65536 bytes is the default value from the SDP spec. Also,
-      //       every implementation we know supports receiving 65536 bytes.
-      var maxMessageSize = 65536;
-
-      // FF 57 has a slightly incorrect default remote max message size, so
-      // we need to adjust it here to avoid a failure when sending.
-      // See: https://bugzilla.mozilla.org/show_bug.cgi?id=1425697
-      if (browserDetails.browser === 'firefox'
-           && browserDetails.version === 57) {
-        maxMessageSize = 65535;
-      }
-
-      var match = SDPUtils.matchPrefix(description.sdp, 'a=max-message-size:');
-      if (match.length > 0) {
-        maxMessageSize = parseInt(match[0].substr(19), 10);
-      } else if (browserDetails.browser === 'firefox' &&
-                  remoteIsFirefox !== -1) {
-        // If the maximum message size is not present in the remote SDP and
-        // both local and remote are Firefox, the remote peer can receive
-        // ~2 GiB.
-        maxMessageSize = 2147483637;
-      }
-      return maxMessageSize;
-    };
-
-    var origSetRemoteDescription =
-        window.RTCPeerConnection.prototype.setRemoteDescription;
-    window.RTCPeerConnection.prototype.setRemoteDescription = function() {
-      var pc = this;
-      pc._sctp = null;
-
-      if (sctpInDescription(arguments[0])) {
-        // Check if the remote is FF.
-        var isFirefox = getRemoteFirefoxVersion(arguments[0]);
-
-        // Get the maximum message size the local peer is capable of sending
-        var canSendMMS = getCanSendMaxMessageSize(isFirefox);
-
-        // Get the maximum message size of the remote peer.
-        var remoteMMS = getMaxMessageSize(arguments[0], isFirefox);
-
-        // Determine final maximum message size
-        var maxMessageSize;
-        if (canSendMMS === 0 && remoteMMS === 0) {
-          maxMessageSize = Number.POSITIVE_INFINITY;
-        } else if (canSendMMS === 0 || remoteMMS === 0) {
-          maxMessageSize = Math.max(canSendMMS, remoteMMS);
-        } else {
-          maxMessageSize = Math.min(canSendMMS, remoteMMS);
-        }
-
-        // Create a dummy RTCSctpTransport object and the 'maxMessageSize'
-        // attribute.
-        var sctp = {};
-        Object.defineProperty(sctp, 'maxMessageSize', {
-          get: function() {
-            return maxMessageSize;
-          }
-        });
-        pc._sctp = sctp;
-      }
-
-      return origSetRemoteDescription.apply(pc, arguments);
-    };
-  },
-
-  shimSendThrowTypeError: function(window) {
-    if (!(window.RTCPeerConnection &&
-        'createDataChannel' in window.RTCPeerConnection.prototype)) {
-      return;
-    }
-
-    // Note: Although Firefox >= 57 has a native implementation, the maximum
-    //       message size can be reset for all data channels at a later stage.
-    //       See: https://bugzilla.mozilla.org/show_bug.cgi?id=1426831
-
-    function wrapDcSend(dc, pc) {
-      var origDataChannelSend = dc.send;
-      dc.send = function() {
-        var data = arguments[0];
-        var length = data.length || data.size || data.byteLength;
-        if (dc.readyState === 'open' &&
-            pc.sctp && length > pc.sctp.maxMessageSize) {
-          throw new TypeError('Message too large (can send a maximum of ' +
-            pc.sctp.maxMessageSize + ' bytes)');
-        }
-        return origDataChannelSend.apply(dc, arguments);
-      };
-    }
-    var origCreateDataChannel =
-      window.RTCPeerConnection.prototype.createDataChannel;
-    window.RTCPeerConnection.prototype.createDataChannel = function() {
-      var pc = this;
-      var dataChannel = origCreateDataChannel.apply(pc, arguments);
-      wrapDcSend(dataChannel, pc);
-      return dataChannel;
-    };
-    utils.wrapPeerConnectionEvent(window, 'datachannel', function(e) {
-      wrapDcSend(e.channel, e.target);
-      return e;
-    });
-  }
-};
-
-},{"./utils":27,"sdp":15}],21:[function(require,module,exports){
-/*
- *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree.
- */
- /* eslint-env node */
-'use strict';
-
-var utils = require('../utils');
-var filterIceServers = require('./filtericeservers');
-var shimRTCPeerConnection = require('rtcpeerconnection-shim');
-
-module.exports = {
-  shimGetUserMedia: require('./getusermedia'),
-  shimPeerConnection: function(window) {
-    var browserDetails = utils.detectBrowser(window);
-
-    if (window.RTCIceGatherer) {
-      if (!window.RTCIceCandidate) {
-        window.RTCIceCandidate = function(args) {
-          return args;
-        };
-      }
-      if (!window.RTCSessionDescription) {
-        window.RTCSessionDescription = function(args) {
-          return args;
-        };
-      }
-      // this adds an additional event listener to MediaStrackTrack that signals
-      // when a tracks enabled property was changed. Workaround for a bug in
-      // addStream, see below. No longer required in 15025+
-      if (browserDetails.version < 15025) {
-        var origMSTEnabled = Object.getOwnPropertyDescriptor(
-            window.MediaStreamTrack.prototype, 'enabled');
-        Object.defineProperty(window.MediaStreamTrack.prototype, 'enabled', {
-          set: function(value) {
-            origMSTEnabled.set.call(this, value);
-            var ev = new Event('enabled');
-            ev.enabled = value;
-            this.dispatchEvent(ev);
-          }
-        });
-      }
-    }
-
-    // ORTC defines the DTMF sender a bit different.
-    // https://github.com/w3c/ortc/issues/714
-    if (window.RTCRtpSender && !('dtmf' in window.RTCRtpSender.prototype)) {
-      Object.defineProperty(window.RTCRtpSender.prototype, 'dtmf', {
-        get: function() {
-          if (this._dtmf === undefined) {
-            if (this.track.kind === 'audio') {
-              this._dtmf = new window.RTCDtmfSender(this);
-            } else if (this.track.kind === 'video') {
-              this._dtmf = null;
-            }
-          }
-          return this._dtmf;
-        }
-      });
-    }
-    // Edge currently only implements the RTCDtmfSender, not the
-    // RTCDTMFSender alias. See http://draft.ortc.org/#rtcdtmfsender2*
-    if (window.RTCDtmfSender && !window.RTCDTMFSender) {
-      window.RTCDTMFSender = window.RTCDtmfSender;
-    }
-
-    var RTCPeerConnectionShim = shimRTCPeerConnection(window,
-        browserDetails.version);
-    window.RTCPeerConnection = function(config) {
-      if (config && config.iceServers) {
-        config.iceServers = filterIceServers(config.iceServers);
-      }
-      return new RTCPeerConnectionShim(config);
-    };
-    window.RTCPeerConnection.prototype = RTCPeerConnectionShim.prototype;
-  },
-  shimReplaceTrack: function(window) {
-    // ORTC has replaceTrack -- https://github.com/w3c/ortc/issues/614
-    if (window.RTCRtpSender &&
-        !('replaceTrack' in window.RTCRtpSender.prototype)) {
-      window.RTCRtpSender.prototype.replaceTrack =
-          window.RTCRtpSender.prototype.setTrack;
-    }
-  }
-};
-
-},{"../utils":27,"./filtericeservers":22,"./getusermedia":23,"rtcpeerconnection-shim":14}],22:[function(require,module,exports){
-/*
- *  Copyright (c) 2018 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree.
- */
- /* eslint-env node */
-'use strict';
-
-var utils = require('../utils');
-// Edge does not like
-// 1) stun: filtered after 14393 unless ?transport=udp is present
-// 2) turn: that does not have all of turn:host:port?transport=udp
-// 3) turn: with ipv6 addresses
-// 4) turn: occurring muliple times
-module.exports = function(iceServers, edgeVersion) {
-  var hasTurn = false;
-  iceServers = JSON.parse(JSON.stringify(iceServers));
-  return iceServers.filter(function(server) {
-    if (server && (server.urls || server.url)) {
-      var urls = server.urls || server.url;
-      if (server.url && !server.urls) {
-        utils.deprecated('RTCIceServer.url', 'RTCIceServer.urls');
-      }
-      var isString = typeof urls === 'string';
-      if (isString) {
-        urls = [urls];
-      }
-      urls = urls.filter(function(url) {
-        var validTurn = url.indexOf('turn:') === 0 &&
-            url.indexOf('transport=udp') !== -1 &&
-            url.indexOf('turn:[') === -1 &&
-            !hasTurn;
-
-        if (validTurn) {
-          hasTurn = true;
-          return true;
-        }
-        return url.indexOf('stun:') === 0 && edgeVersion >= 14393 &&
-            url.indexOf('?transport=udp') === -1;
-      });
-
-      delete server.url;
-      server.urls = isString ? urls[0] : urls;
-      return !!urls.length;
-    }
-  });
-};
-
-},{"../utils":27}],23:[function(require,module,exports){
-/*
- *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree.
- */
- /* eslint-env node */
-'use strict';
-
-// Expose public methods.
-module.exports = function(window) {
-  var navigator = window && window.navigator;
-
-  var shimError_ = function(e) {
-    return {
-      name: {PermissionDeniedError: 'NotAllowedError'}[e.name] || e.name,
-      message: e.message,
-      constraint: e.constraint,
-      toString: function() {
-        return this.name;
-      }
-    };
-  };
-
-  // getUserMedia error shim.
-  var origGetUserMedia = navigator.mediaDevices.getUserMedia.
-      bind(navigator.mediaDevices);
-  navigator.mediaDevices.getUserMedia = function(c) {
-    return origGetUserMedia(c).catch(function(e) {
-      return Promise.reject(shimError_(e));
-    });
-  };
-};
-
-},{}],24:[function(require,module,exports){
-/*
- *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree.
- */
- /* eslint-env node */
-'use strict';
-
-var utils = require('../utils');
-
-module.exports = {
-  shimGetUserMedia: require('./getusermedia'),
-  shimOnTrack: function(window) {
-    if (typeof window === 'object' && window.RTCPeerConnection && !('ontrack' in
-        window.RTCPeerConnection.prototype)) {
-      Object.defineProperty(window.RTCPeerConnection.prototype, 'ontrack', {
-        get: function() {
-          return this._ontrack;
-        },
-        set: function(f) {
-          if (this._ontrack) {
-            this.removeEventListener('track', this._ontrack);
-            this.removeEventListener('addstream', this._ontrackpoly);
-          }
-          this.addEventListener('track', this._ontrack = f);
-          this.addEventListener('addstream', this._ontrackpoly = function(e) {
-            e.stream.getTracks().forEach(function(track) {
-              var event = new Event('track');
-              event.track = track;
-              event.receiver = {track: track};
-              event.transceiver = {receiver: event.receiver};
-              event.streams = [e.stream];
-              this.dispatchEvent(event);
-            }.bind(this));
-          }.bind(this));
-        },
-        enumerable: true,
-        configurable: true
-      });
-    }
-    if (typeof window === 'object' && window.RTCTrackEvent &&
-        ('receiver' in window.RTCTrackEvent.prototype) &&
-        !('transceiver' in window.RTCTrackEvent.prototype)) {
-      Object.defineProperty(window.RTCTrackEvent.prototype, 'transceiver', {
-        get: function() {
-          return {receiver: this.receiver};
-        }
-      });
-    }
-  },
-
-  shimSourceObject: function(window) {
-    // Firefox has supported mozSrcObject since FF22, unprefixed in 42.
-    if (typeof window === 'object') {
-      if (window.HTMLMediaElement &&
-        !('srcObject' in window.HTMLMediaElement.prototype)) {
-        // Shim the srcObject property, once, when HTMLMediaElement is found.
-        Object.defineProperty(window.HTMLMediaElement.prototype, 'srcObject', {
-          get: function() {
-            return this.mozSrcObject;
-          },
-          set: function(stream) {
-            this.mozSrcObject = stream;
-          }
-        });
-      }
-    }
-  },
-
-  shimPeerConnection: function(window) {
-    var browserDetails = utils.detectBrowser(window);
-
-    if (typeof window !== 'object' || !(window.RTCPeerConnection ||
-        window.mozRTCPeerConnection)) {
-      return; // probably media.peerconnection.enabled=false in about:config
-    }
-    // The RTCPeerConnection object.
-    if (!window.RTCPeerConnection) {
-      window.RTCPeerConnection = function(pcConfig, pcConstraints) {
-        if (browserDetails.version < 38) {
-          // .urls is not supported in FF < 38.
-          // create RTCIceServers with a single url.
-          if (pcConfig && pcConfig.iceServers) {
-            var newIceServers = [];
-            for (var i = 0; i < pcConfig.iceServers.length; i++) {
-              var server = pcConfig.iceServers[i];
-              if (server.hasOwnProperty('urls')) {
-                for (var j = 0; j < server.urls.length; j++) {
-                  var newServer = {
-                    url: server.urls[j]
-                  };
-                  if (server.urls[j].indexOf('turn') === 0) {
-                    newServer.username = server.username;
-                    newServer.credential = server.credential;
-                  }
-                  newIceServers.push(newServer);
-                }
-              } else {
-                newIceServers.push(pcConfig.iceServers[i]);
-              }
-            }
-            pcConfig.iceServers = newIceServers;
-          }
-        }
-        return new window.mozRTCPeerConnection(pcConfig, pcConstraints);
-      };
-      window.RTCPeerConnection.prototype =
-          window.mozRTCPeerConnection.prototype;
-
-      // wrap static methods. Currently just generateCertificate.
-      if (window.mozRTCPeerConnection.generateCertificate) {
-        Object.defineProperty(window.RTCPeerConnection, 'generateCertificate', {
-          get: function() {
-            return window.mozRTCPeerConnection.generateCertificate;
-          }
-        });
-      }
-
-      window.RTCSessionDescription = window.mozRTCSessionDescription;
-      window.RTCIceCandidate = window.mozRTCIceCandidate;
-    }
-
-    // shim away need for obsolete RTCIceCandidate/RTCSessionDescription.
-    ['setLocalDescription', 'setRemoteDescription', 'addIceCandidate']
-        .forEach(function(method) {
-          var nativeMethod = window.RTCPeerConnection.prototype[method];
-          window.RTCPeerConnection.prototype[method] = function() {
-            arguments[0] = new ((method === 'addIceCandidate') ?
-                window.RTCIceCandidate :
-                window.RTCSessionDescription)(arguments[0]);
-            return nativeMethod.apply(this, arguments);
-          };
-        });
-
-    // support for addIceCandidate(null or undefined)
-    var nativeAddIceCandidate =
-        window.RTCPeerConnection.prototype.addIceCandidate;
-    window.RTCPeerConnection.prototype.addIceCandidate = function() {
-      if (!arguments[0]) {
-        if (arguments[1]) {
-          arguments[1].apply(null);
-        }
-        return Promise.resolve();
-      }
-      return nativeAddIceCandidate.apply(this, arguments);
-    };
-
-    // shim getStats with maplike support
-    var makeMapStats = function(stats) {
-      var map = new Map();
-      Object.keys(stats).forEach(function(key) {
-        map.set(key, stats[key]);
-        map[key] = stats[key];
-      });
-      return map;
-    };
-
-    var modernStatsTypes = {
-      inboundrtp: 'inbound-rtp',
-      outboundrtp: 'outbound-rtp',
-      candidatepair: 'candidate-pair',
-      localcandidate: 'local-candidate',
-      remotecandidate: 'remote-candidate'
-    };
-
-    var nativeGetStats = window.RTCPeerConnection.prototype.getStats;
-    window.RTCPeerConnection.prototype.getStats = function(
-      selector,
-      onSucc,
-      onErr
-    ) {
-      return nativeGetStats.apply(this, [selector || null])
-        .then(function(stats) {
-          if (browserDetails.version < 48) {
-            stats = makeMapStats(stats);
-          }
-          if (browserDetails.version < 53 && !onSucc) {
-            // Shim only promise getStats with spec-hyphens in type names
-            // Leave callback version alone; misc old uses of forEach before Map
-            try {
-              stats.forEach(function(stat) {
-                stat.type = modernStatsTypes[stat.type] || stat.type;
-              });
-            } catch (e) {
-              if (e.name !== 'TypeError') {
-                throw e;
-              }
-              // Avoid TypeError: "type" is read-only, in old versions. 34-43ish
-              stats.forEach(function(stat, i) {
-                stats.set(i, Object.assign({}, stat, {
-                  type: modernStatsTypes[stat.type] || stat.type
-                }));
-              });
-            }
-          }
-          return stats;
-        })
-        .then(onSucc, onErr);
-    };
-  },
-
-  shimSenderGetStats: function(window) {
-    if (!(typeof window === 'object' && window.RTCPeerConnection &&
-        window.RTCRtpSender)) {
-      return;
-    }
-    if (window.RTCRtpSender && 'getStats' in window.RTCRtpSender.prototype) {
-      return;
-    }
-    var origGetSenders = window.RTCPeerConnection.prototype.getSenders;
-    if (origGetSenders) {
-      window.RTCPeerConnection.prototype.getSenders = function() {
-        var pc = this;
-        var senders = origGetSenders.apply(pc, []);
-        senders.forEach(function(sender) {
-          sender._pc = pc;
-        });
-        return senders;
-      };
-    }
-
-    var origAddTrack = window.RTCPeerConnection.prototype.addTrack;
-    if (origAddTrack) {
-      window.RTCPeerConnection.prototype.addTrack = function() {
-        var sender = origAddTrack.apply(this, arguments);
-        sender._pc = this;
-        return sender;
-      };
-    }
-    window.RTCRtpSender.prototype.getStats = function() {
-      return this.track ? this._pc.getStats(this.track) :
-          Promise.resolve(new Map());
-    };
-  },
-
-  shimReceiverGetStats: function(window) {
-    if (!(typeof window === 'object' && window.RTCPeerConnection &&
-        window.RTCRtpSender)) {
-      return;
-    }
-    if (window.RTCRtpSender && 'getStats' in window.RTCRtpReceiver.prototype) {
-      return;
-    }
-    var origGetReceivers = window.RTCPeerConnection.prototype.getReceivers;
-    if (origGetReceivers) {
-      window.RTCPeerConnection.prototype.getReceivers = function() {
-        var pc = this;
-        var receivers = origGetReceivers.apply(pc, []);
-        receivers.forEach(function(receiver) {
-          receiver._pc = pc;
-        });
-        return receivers;
-      };
-    }
-    utils.wrapPeerConnectionEvent(window, 'track', function(e) {
-      e.receiver._pc = e.srcElement;
-      return e;
-    });
-    window.RTCRtpReceiver.prototype.getStats = function() {
-      return this._pc.getStats(this.track);
-    };
-  },
-
-  shimRemoveStream: function(window) {
-    if (!window.RTCPeerConnection ||
-        'removeStream' in window.RTCPeerConnection.prototype) {
-      return;
-    }
-    window.RTCPeerConnection.prototype.removeStream = function(stream) {
-      var pc = this;
-      utils.deprecated('removeStream', 'removeTrack');
-      this.getSenders().forEach(function(sender) {
-        if (sender.track && stream.getTracks().indexOf(sender.track) !== -1) {
-          pc.removeTrack(sender);
-        }
-      });
-    };
-  },
-
-  shimRTCDataChannel: function(window) {
-    // rename DataChannel to RTCDataChannel (native fix in FF60):
-    // https://bugzilla.mozilla.org/show_bug.cgi?id=1173851
-    if (window.DataChannel && !window.RTCDataChannel) {
-      window.RTCDataChannel = window.DataChannel;
-    }
-  },
-
-  shimGetDisplayMedia: function(window, preferredMediaSource) {
-    if ('getDisplayMedia' in window.navigator) {
-      return;
-    }
-    navigator.getDisplayMedia = function(constraints) {
-      if (!(constraints && constraints.video)) {
-        var err = new DOMException('getDisplayMedia without video ' +
-            'constraints is undefined');
-        err.name = 'NotFoundError';
-        // from https://heycam.github.io/webidl/#idl-DOMException-error-names
-        err.code = 8;
-        return Promise.reject(err);
-      }
-      if (constraints.video === true) {
-        constraints.video = {mediaSource: preferredMediaSource};
-      } else {
-        constraints.video.mediaSource = preferredMediaSource;
-      }
-      return navigator.mediaDevices.getUserMedia(constraints);
-    };
-  }
-};
-
-},{"../utils":27,"./getusermedia":25}],25:[function(require,module,exports){
-/*
- *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree.
- */
- /* eslint-env node */
-'use strict';
-
-var utils = require('../utils');
-var logging = utils.log;
-
-// Expose public methods.
-module.exports = function(window) {
-  var browserDetails = utils.detectBrowser(window);
-  var navigator = window && window.navigator;
-  var MediaStreamTrack = window && window.MediaStreamTrack;
-
-  var shimError_ = function(e) {
-    return {
-      name: {
-        InternalError: 'NotReadableError',
-        NotSupportedError: 'TypeError',
-        PermissionDeniedError: 'NotAllowedError',
-        SecurityError: 'NotAllowedError'
-      }[e.name] || e.name,
-      message: {
-        'The operation is insecure.': 'The request is not allowed by the ' +
-        'user agent or the platform in the current context.'
-      }[e.message] || e.message,
-      constraint: e.constraint,
-      toString: function() {
-        return this.name + (this.message && ': ') + this.message;
-      }
-    };
-  };
-
-  // getUserMedia constraints shim.
-  var getUserMedia_ = function(constraints, onSuccess, onError) {
-    var constraintsToFF37_ = function(c) {
-      if (typeof c !== 'object' || c.require) {
-        return c;
-      }
-      var require = [];
-      Object.keys(c).forEach(function(key) {
-        if (key === 'require' || key === 'advanced' || key === 'mediaSource') {
-          return;
-        }
-        var r = c[key] = (typeof c[key] === 'object') ?
-            c[key] : {ideal: c[key]};
-        if (r.min !== undefined ||
-            r.max !== undefined || r.exact !== undefined) {
-          require.push(key);
-        }
-        if (r.exact !== undefined) {
-          if (typeof r.exact === 'number') {
-            r. min = r.max = r.exact;
-          } else {
-            c[key] = r.exact;
-          }
-          delete r.exact;
-        }
-        if (r.ideal !== undefined) {
-          c.advanced = c.advanced || [];
-          var oc = {};
-          if (typeof r.ideal === 'number') {
-            oc[key] = {min: r.ideal, max: r.ideal};
-          } else {
-            oc[key] = r.ideal;
-          }
-          c.advanced.push(oc);
-          delete r.ideal;
-          if (!Object.keys(r).length) {
-            delete c[key];
-          }
-        }
-      });
-      if (require.length) {
-        c.require = require;
-      }
-      return c;
-    };
-    constraints = JSON.parse(JSON.stringify(constraints));
-    if (browserDetails.version < 38) {
-      logging('spec: ' + JSON.stringify(constraints));
-      if (constraints.audio) {
-        constraints.audio = constraintsToFF37_(constraints.audio);
-      }
-      if (constraints.video) {
-        constraints.video = constraintsToFF37_(constraints.video);
-      }
-      logging('ff37: ' + JSON.stringify(constraints));
-    }
-    return navigator.mozGetUserMedia(constraints, onSuccess, function(e) {
-      onError(shimError_(e));
-    });
-  };
-
-  // Returns the result of getUserMedia as a Promise.
-  var getUserMediaPromise_ = function(constraints) {
-    return new Promise(function(resolve, reject) {
-      getUserMedia_(constraints, resolve, reject);
-    });
-  };
-
-  // Shim for mediaDevices on older versions.
-  if (!navigator.mediaDevices) {
-    navigator.mediaDevices = {getUserMedia: getUserMediaPromise_,
-      addEventListener: function() { },
-      removeEventListener: function() { }
-    };
-  }
-  navigator.mediaDevices.enumerateDevices =
-      navigator.mediaDevices.enumerateDevices || function() {
-        return new Promise(function(resolve) {
-          var infos = [
-            {kind: 'audioinput', deviceId: 'default', label: '', groupId: ''},
-            {kind: 'videoinput', deviceId: 'default', label: '', groupId: ''}
-          ];
-          resolve(infos);
-        });
-      };
-
-  if (browserDetails.version < 41) {
-    // Work around http://bugzil.la/1169665
-    var orgEnumerateDevices =
-        navigator.mediaDevices.enumerateDevices.bind(navigator.mediaDevices);
-    navigator.mediaDevices.enumerateDevices = function() {
-      return orgEnumerateDevices().then(undefined, function(e) {
-        if (e.name === 'NotFoundError') {
-          return [];
-        }
-        throw e;
-      });
-    };
-  }
-  if (browserDetails.version < 49) {
-    var origGetUserMedia = navigator.mediaDevices.getUserMedia.
-        bind(navigator.mediaDevices);
-    navigator.mediaDevices.getUserMedia = function(c) {
-      return origGetUserMedia(c).then(function(stream) {
-        // Work around https://bugzil.la/802326
-        if (c.audio && !stream.getAudioTracks().length ||
-            c.video && !stream.getVideoTracks().length) {
-          stream.getTracks().forEach(function(track) {
-            track.stop();
-          });
-          throw new DOMException('The object can not be found here.',
-                                 'NotFoundError');
-        }
-        return stream;
-      }, function(e) {
-        return Promise.reject(shimError_(e));
-      });
-    };
-  }
-  if (!(browserDetails.version > 55 &&
-      'autoGainControl' in navigator.mediaDevices.getSupportedConstraints())) {
-    var remap = function(obj, a, b) {
-      if (a in obj && !(b in obj)) {
-        obj[b] = obj[a];
-        delete obj[a];
-      }
-    };
-
-    var nativeGetUserMedia = navigator.mediaDevices.getUserMedia.
-        bind(navigator.mediaDevices);
-    navigator.mediaDevices.getUserMedia = function(c) {
-      if (typeof c === 'object' && typeof c.audio === 'object') {
-        c = JSON.parse(JSON.stringify(c));
-        remap(c.audio, 'autoGainControl', 'mozAutoGainControl');
-        remap(c.audio, 'noiseSuppression', 'mozNoiseSuppression');
-      }
-      return nativeGetUserMedia(c);
-    };
-
-    if (MediaStreamTrack && MediaStreamTrack.prototype.getSettings) {
-      var nativeGetSettings = MediaStreamTrack.prototype.getSettings;
-      MediaStreamTrack.prototype.getSettings = function() {
-        var obj = nativeGetSettings.apply(this, arguments);
-        remap(obj, 'mozAutoGainControl', 'autoGainControl');
-        remap(obj, 'mozNoiseSuppression', 'noiseSuppression');
-        return obj;
-      };
-    }
-
-    if (MediaStreamTrack && MediaStreamTrack.prototype.applyConstraints) {
-      var nativeApplyConstraints = MediaStreamTrack.prototype.applyConstraints;
-      MediaStreamTrack.prototype.applyConstraints = function(c) {
-        if (this.kind === 'audio' && typeof c === 'object') {
-          c = JSON.parse(JSON.stringify(c));
-          remap(c, 'autoGainControl', 'mozAutoGainControl');
-          remap(c, 'noiseSuppression', 'mozNoiseSuppression');
-        }
-        return nativeApplyConstraints.apply(this, [c]);
-      };
-    }
-  }
-  navigator.getUserMedia = function(constraints, onSuccess, onError) {
-    if (browserDetails.version < 44) {
-      return getUserMedia_(constraints, onSuccess, onError);
-    }
-    // Replace Firefox 44+'s deprecation warning with unprefixed version.
-    utils.deprecated('navigator.getUserMedia',
-        'navigator.mediaDevices.getUserMedia');
-    navigator.mediaDevices.getUserMedia(constraints).then(onSuccess, onError);
-  };
-};
-
-},{"../utils":27}],26:[function(require,module,exports){
-/*
- *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree.
- */
-'use strict';
-var utils = require('../utils');
-
-module.exports = {
-  shimLocalStreamsAPI: function(window) {
-    if (typeof window !== 'object' || !window.RTCPeerConnection) {
-      return;
-    }
-    if (!('getLocalStreams' in window.RTCPeerConnection.prototype)) {
-      window.RTCPeerConnection.prototype.getLocalStreams = function() {
-        if (!this._localStreams) {
-          this._localStreams = [];
-        }
-        return this._localStreams;
-      };
-    }
-    if (!('getStreamById' in window.RTCPeerConnection.prototype)) {
-      window.RTCPeerConnection.prototype.getStreamById = function(id) {
-        var result = null;
-        if (this._localStreams) {
-          this._localStreams.forEach(function(stream) {
-            if (stream.id === id) {
-              result = stream;
-            }
-          });
-        }
-        if (this._remoteStreams) {
-          this._remoteStreams.forEach(function(stream) {
-            if (stream.id === id) {
-              result = stream;
-            }
-          });
-        }
-        return result;
-      };
-    }
-    if (!('addStream' in window.RTCPeerConnection.prototype)) {
-      var _addTrack = window.RTCPeerConnection.prototype.addTrack;
-      window.RTCPeerConnection.prototype.addStream = function(stream) {
-        if (!this._localStreams) {
-          this._localStreams = [];
-        }
-        if (this._localStreams.indexOf(stream) === -1) {
-          this._localStreams.push(stream);
-        }
-        var pc = this;
-        stream.getTracks().forEach(function(track) {
-          _addTrack.call(pc, track, stream);
-        });
-      };
-
-      window.RTCPeerConnection.prototype.addTrack = function(track, stream) {
-        if (stream) {
-          if (!this._localStreams) {
-            this._localStreams = [stream];
-          } else if (this._localStreams.indexOf(stream) === -1) {
-            this._localStreams.push(stream);
-          }
-        }
-        return _addTrack.call(this, track, stream);
-      };
-    }
-    if (!('removeStream' in window.RTCPeerConnection.prototype)) {
-      window.RTCPeerConnection.prototype.removeStream = function(stream) {
-        if (!this._localStreams) {
-          this._localStreams = [];
-        }
-        var index = this._localStreams.indexOf(stream);
-        if (index === -1) {
-          return;
-        }
-        this._localStreams.splice(index, 1);
-        var pc = this;
-        var tracks = stream.getTracks();
-        this.getSenders().forEach(function(sender) {
-          if (tracks.indexOf(sender.track) !== -1) {
-            pc.removeTrack(sender);
-          }
-        });
-      };
-    }
-  },
-  shimRemoteStreamsAPI: function(window) {
-    if (typeof window !== 'object' || !window.RTCPeerConnection) {
-      return;
-    }
-    if (!('getRemoteStreams' in window.RTCPeerConnection.prototype)) {
-      window.RTCPeerConnection.prototype.getRemoteStreams = function() {
-        return this._remoteStreams ? this._remoteStreams : [];
-      };
-    }
-    if (!('onaddstream' in window.RTCPeerConnection.prototype)) {
-      Object.defineProperty(window.RTCPeerConnection.prototype, 'onaddstream', {
-        get: function() {
-          return this._onaddstream;
-        },
-        set: function(f) {
-          if (this._onaddstream) {
-            this.removeEventListener('addstream', this._onaddstream);
-          }
-          this.addEventListener('addstream', this._onaddstream = f);
-        }
-      });
-      var origSetRemoteDescription =
-          window.RTCPeerConnection.prototype.setRemoteDescription;
-      window.RTCPeerConnection.prototype.setRemoteDescription = function() {
-        var pc = this;
-        if (!this._onaddstreampoly) {
-          this.addEventListener('track', this._onaddstreampoly = function(e) {
-            e.streams.forEach(function(stream) {
-              if (!pc._remoteStreams) {
-                pc._remoteStreams = [];
-              }
-              if (pc._remoteStreams.indexOf(stream) >= 0) {
-                return;
-              }
-              pc._remoteStreams.push(stream);
-              var event = new Event('addstream');
-              event.stream = stream;
-              pc.dispatchEvent(event);
-            });
-          });
-        }
-        return origSetRemoteDescription.apply(pc, arguments);
-      };
-    }
-  },
-  shimCallbacksAPI: function(window) {
-    if (typeof window !== 'object' || !window.RTCPeerConnection) {
-      return;
-    }
-    var prototype = window.RTCPeerConnection.prototype;
-    var createOffer = prototype.createOffer;
-    var createAnswer = prototype.createAnswer;
-    var setLocalDescription = prototype.setLocalDescription;
-    var setRemoteDescription = prototype.setRemoteDescription;
-    var addIceCandidate = prototype.addIceCandidate;
-
-    prototype.createOffer = function(successCallback, failureCallback) {
-      var options = (arguments.length >= 2) ? arguments[2] : arguments[0];
-      var promise = createOffer.apply(this, [options]);
-      if (!failureCallback) {
-        return promise;
-      }
-      promise.then(successCallback, failureCallback);
-      return Promise.resolve();
-    };
-
-    prototype.createAnswer = function(successCallback, failureCallback) {
-      var options = (arguments.length >= 2) ? arguments[2] : arguments[0];
-      var promise = createAnswer.apply(this, [options]);
-      if (!failureCallback) {
-        return promise;
-      }
-      promise.then(successCallback, failureCallback);
-      return Promise.resolve();
-    };
-
-    var withCallback = function(description, successCallback, failureCallback) {
-      var promise = setLocalDescription.apply(this, [description]);
-      if (!failureCallback) {
-        return promise;
-      }
-      promise.then(successCallback, failureCallback);
-      return Promise.resolve();
-    };
-    prototype.setLocalDescription = withCallback;
-
-    withCallback = function(description, successCallback, failureCallback) {
-      var promise = setRemoteDescription.apply(this, [description]);
-      if (!failureCallback) {
-        return promise;
-      }
-      promise.then(successCallback, failureCallback);
-      return Promise.resolve();
-    };
-    prototype.setRemoteDescription = withCallback;
-
-    withCallback = function(candidate, successCallback, failureCallback) {
-      var promise = addIceCandidate.apply(this, [candidate]);
-      if (!failureCallback) {
-        return promise;
-      }
-      promise.then(successCallback, failureCallback);
-      return Promise.resolve();
-    };
-    prototype.addIceCandidate = withCallback;
-  },
-  shimGetUserMedia: function(window) {
-    var navigator = window && window.navigator;
-
-    if (!navigator.getUserMedia) {
-      if (navigator.webkitGetUserMedia) {
-        navigator.getUserMedia = navigator.webkitGetUserMedia.bind(navigator);
-      } else if (navigator.mediaDevices &&
-          navigator.mediaDevices.getUserMedia) {
-        navigator.getUserMedia = function(constraints, cb, errcb) {
-          navigator.mediaDevices.getUserMedia(constraints)
-          .then(cb, errcb);
-        }.bind(navigator);
-      }
-    }
-  },
-  shimRTCIceServerUrls: function(window) {
-    // migrate from non-spec RTCIceServer.url to RTCIceServer.urls
-    var OrigPeerConnection = window.RTCPeerConnection;
-    window.RTCPeerConnection = function(pcConfig, pcConstraints) {
-      if (pcConfig && pcConfig.iceServers) {
-        var newIceServers = [];
-        for (var i = 0; i < pcConfig.iceServers.length; i++) {
-          var server = pcConfig.iceServers[i];
-          if (!server.hasOwnProperty('urls') &&
-              server.hasOwnProperty('url')) {
-            utils.deprecated('RTCIceServer.url', 'RTCIceServer.urls');
-            server = JSON.parse(JSON.stringify(server));
-            server.urls = server.url;
-            delete server.url;
-            newIceServers.push(server);
-          } else {
-            newIceServers.push(pcConfig.iceServers[i]);
-          }
-        }
-        pcConfig.iceServers = newIceServers;
-      }
-      return new OrigPeerConnection(pcConfig, pcConstraints);
-    };
-    window.RTCPeerConnection.prototype = OrigPeerConnection.prototype;
-    // wrap static methods. Currently just generateCertificate.
-    if ('generateCertificate' in window.RTCPeerConnection) {
-      Object.defineProperty(window.RTCPeerConnection, 'generateCertificate', {
-        get: function() {
-          return OrigPeerConnection.generateCertificate;
-        }
-      });
-    }
-  },
-  shimTrackEventTransceiver: function(window) {
-    // Add event.transceiver member over deprecated event.receiver
-    if (typeof window === 'object' && window.RTCPeerConnection &&
-        ('receiver' in window.RTCTrackEvent.prototype) &&
-        // can't check 'transceiver' in window.RTCTrackEvent.prototype, as it is
-        // defined for some reason even when window.RTCTransceiver is not.
-        !window.RTCTransceiver) {
-      Object.defineProperty(window.RTCTrackEvent.prototype, 'transceiver', {
-        get: function() {
-          return {receiver: this.receiver};
-        }
-      });
-    }
-  },
-
-  shimCreateOfferLegacy: function(window) {
-    var origCreateOffer = window.RTCPeerConnection.prototype.createOffer;
-    window.RTCPeerConnection.prototype.createOffer = function(offerOptions) {
-      var pc = this;
-      if (offerOptions) {
-        if (typeof offerOptions.offerToReceiveAudio !== 'undefined') {
-          // support bit values
-          offerOptions.offerToReceiveAudio = !!offerOptions.offerToReceiveAudio;
-        }
-        var audioTransceiver = pc.getTransceivers().find(function(transceiver) {
-          return transceiver.sender.track &&
-              transceiver.sender.track.kind === 'audio';
-        });
-        if (offerOptions.offerToReceiveAudio === false && audioTransceiver) {
-          if (audioTransceiver.direction === 'sendrecv') {
-            if (audioTransceiver.setDirection) {
-              audioTransceiver.setDirection('sendonly');
-            } else {
-              audioTransceiver.direction = 'sendonly';
-            }
-          } else if (audioTransceiver.direction === 'recvonly') {
-            if (audioTransceiver.setDirection) {
-              audioTransceiver.setDirection('inactive');
-            } else {
-              audioTransceiver.direction = 'inactive';
-            }
-          }
-        } else if (offerOptions.offerToReceiveAudio === true &&
-            !audioTransceiver) {
-          pc.addTransceiver('audio');
-        }
-
-
-        if (typeof offerOptions.offerToReceiveVideo !== 'undefined') {
-          // support bit values
-          offerOptions.offerToReceiveVideo = !!offerOptions.offerToReceiveVideo;
-        }
-        var videoTransceiver = pc.getTransceivers().find(function(transceiver) {
-          return transceiver.sender.track &&
-              transceiver.sender.track.kind === 'video';
-        });
-        if (offerOptions.offerToReceiveVideo === false && videoTransceiver) {
-          if (videoTransceiver.direction === 'sendrecv') {
-            videoTransceiver.setDirection('sendonly');
-          } else if (videoTransceiver.direction === 'recvonly') {
-            videoTransceiver.setDirection('inactive');
-          }
-        } else if (offerOptions.offerToReceiveVideo === true &&
-            !videoTransceiver) {
-          pc.addTransceiver('video');
-        }
-      }
-      return origCreateOffer.apply(pc, arguments);
-    };
-  }
-};
-
-},{"../utils":27}],27:[function(require,module,exports){
-/*
- *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree.
- */
- /* eslint-env node */
-'use strict';
-
-var logDisabled_ = true;
-var deprecationWarnings_ = true;
-
-/**
- * Extract browser version out of the provided user agent string.
- *
- * @param {!string} uastring userAgent string.
- * @param {!string} expr Regular expression used as match criteria.
- * @param {!number} pos position in the version string to be returned.
- * @return {!number} browser version.
- */
-function extractVersion(uastring, expr, pos) {
-  var match = uastring.match(expr);
-  return match && match.length >= pos && parseInt(match[pos], 10);
-}
-
-// Wraps the peerconnection event eventNameToWrap in a function
-// which returns the modified event object (or false to prevent
-// the event).
-function wrapPeerConnectionEvent(window, eventNameToWrap, wrapper) {
-  if (!window.RTCPeerConnection) {
-    return;
-  }
-  var proto = window.RTCPeerConnection.prototype;
-  var nativeAddEventListener = proto.addEventListener;
-  proto.addEventListener = function(nativeEventName, cb) {
-    if (nativeEventName !== eventNameToWrap) {
-      return nativeAddEventListener.apply(this, arguments);
-    }
-    var wrappedCallback = function(e) {
-      var modifiedEvent = wrapper(e);
-      if (modifiedEvent) {
-        cb(modifiedEvent);
-      }
-    };
-    this._eventMap = this._eventMap || {};
-    this._eventMap[cb] = wrappedCallback;
-    return nativeAddEventListener.apply(this, [nativeEventName,
-      wrappedCallback]);
-  };
-
-  var nativeRemoveEventListener = proto.removeEventListener;
-  proto.removeEventListener = function(nativeEventName, cb) {
-    if (nativeEventName !== eventNameToWrap || !this._eventMap
-        || !this._eventMap[cb]) {
-      return nativeRemoveEventListener.apply(this, arguments);
-    }
-    var unwrappedCb = this._eventMap[cb];
-    delete this._eventMap[cb];
-    return nativeRemoveEventListener.apply(this, [nativeEventName,
-      unwrappedCb]);
-  };
-
-  Object.defineProperty(proto, 'on' + eventNameToWrap, {
-    get: function() {
-      return this['_on' + eventNameToWrap];
-    },
-    set: function(cb) {
-      if (this['_on' + eventNameToWrap]) {
-        this.removeEventListener(eventNameToWrap,
-            this['_on' + eventNameToWrap]);
-        delete this['_on' + eventNameToWrap];
-      }
-      if (cb) {
-        this.addEventListener(eventNameToWrap,
-            this['_on' + eventNameToWrap] = cb);
-      }
-    },
-    enumerable: true,
-    configurable: true
-  });
-}
-
-// Utility methods.
-module.exports = {
-  extractVersion: extractVersion,
-  wrapPeerConnectionEvent: wrapPeerConnectionEvent,
-  disableLog: function(bool) {
-    if (typeof bool !== 'boolean') {
-      return new Error('Argument type: ' + typeof bool +
-          '. Please use a boolean.');
-    }
-    logDisabled_ = bool;
-    return (bool) ? 'adapter.js logging disabled' :
-        'adapter.js logging enabled';
-  },
-
-  /**
-   * Disable or enable deprecation warnings
-   * @param {!boolean} bool set to true to disable warnings.
-   */
-  disableWarnings: function(bool) {
-    if (typeof bool !== 'boolean') {
-      return new Error('Argument type: ' + typeof bool +
-          '. Please use a boolean.');
-    }
-    deprecationWarnings_ = !bool;
-    return 'adapter.js deprecation warnings ' + (bool ? 'disabled' : 'enabled');
-  },
-
-  log: function() {
-    if (typeof window === 'object') {
-      if (logDisabled_) {
-        return;
-      }
-      if (typeof console !== 'undefined' && typeof console.log === 'function') {
-        console.log.apply(console, arguments);
-      }
-    }
-  },
-
-  /**
-   * Shows a deprecation warning suggesting the modern and spec-compatible API.
-   */
-  deprecated: function(oldMethod, newMethod) {
-    if (!deprecationWarnings_) {
-      return;
-    }
-    console.warn(oldMethod + ' is deprecated, please use ' + newMethod +
-        ' instead.');
-  },
-
-  /**
-   * Browser detector.
-   *
-   * @return {object} result containing browser and version
-   *     properties.
-   */
-  detectBrowser: function(window) {
-    var navigator = window && window.navigator;
-
-    // Returned result object.
-    var result = {};
-    result.browser = null;
-    result.version = null;
-
-    // Fail early if it's not a browser
-    if (typeof window === 'undefined' || !window.navigator) {
-      result.browser = 'Not a browser.';
-      return result;
-    }
-
-    if (navigator.mozGetUserMedia) { // Firefox.
-      result.browser = 'firefox';
-      result.version = extractVersion(navigator.userAgent,
-          /Firefox\/(\d+)\./, 1);
-    } else if (navigator.webkitGetUserMedia) {
-      // Chrome, Chromium, Webview, Opera.
-      // Version matches Chrome/WebRTC version.
-      result.browser = 'chrome';
-      result.version = extractVersion(navigator.userAgent,
-          /Chrom(e|ium)\/(\d+)\./, 2);
-    } else if (navigator.mediaDevices &&
-        navigator.userAgent.match(/Edge\/(\d+).(\d+)$/)) { // Edge.
-      result.browser = 'edge';
-      result.version = extractVersion(navigator.userAgent,
-          /Edge\/(\d+).(\d+)$/, 2);
-    } else if (window.RTCPeerConnection &&
-        navigator.userAgent.match(/AppleWebKit\/(\d+)\./)) { // Safari.
-      result.browser = 'safari';
-      result.version = extractVersion(navigator.userAgent,
-          /AppleWebKit\/(\d+)\./, 1);
-    } else { // Default fallthrough: not supported.
-      result.browser = 'Not a supported browser.';
-      return result;
-    }
-
-    return result;
-  }
-};
-
-},{}]},{},[3]);

test/public/index.html

@@ -1,51 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-
-<head>
-    <meta charset="UTF-8">
-    <meta name="viewport" content="width=device-width, initial-scale=1.0">
-    <meta http-equiv="X-UA-Compatible" content="ie=edge">
-    <title>PeerJS Test</title>
-    <script src="peer.min.js"></script>
-</head>
-
-<body>
-    <div id="id" style="margin: 50px;border: 1px solid red"></div>
-    <div id="data" style="margin: 50px;border: 1px solid green"></div>
-    <div id="log" style="margin: 50px;border: 1px solid blue"></div>
-    <script>
-        var peer = new Peer();
-        // on open will be launch when you successfully connect to PeerServer
-        peer.on('open', function (id) {
-            log("got id " + id)
-            document.querySelector("#id").innerHTML = id
-        });
-        peer.on('connection', function (conn) {
-            log("got new connection")
-            conn.on('data', function (data) {
-                log("got data " + data)
-                document.querySelector("#data").innerHTML = data;
-                log("answering pong")
-                conn.send("pong")
-            });
-        });
-
-        function connect(id) {
-            log("connecting peer " + id)
-            var conn = peer.connect(id);
-            conn.on('open', function () {
-                log("connected to peer " + id)
-                conn.send("ping")
-            });
-            conn.on("data", function (data) {
-                document.querySelector("#data").innerHTML = data;
-            });
-        }
-
-        function log(text) {
-            document.querySelector("#log").innerHTML += text + "<br/>";
-        }
-    </script>
-</body>
-
-</html>