MAM: Always query for newest MAM messages after cached ones have been fetched

The `_converse.connection.restored` check ensured that 1:1 chats
manually opened after tab reload would never get their MAM messages
fetched :facepalm:

src/headless/plugins/mam/index.js

@@ -48,19 +48,13 @@ converse.plugins.add('converse-mam', {
         api.listen.on('enteredNewRoom', muc => muc.features.get('mam_enabled') && fetchNewestMessages(muc));
 
         api.listen.on('chatReconnected', chat => {
-            // XXX: For MUCs, we listen to enteredNewRoom instead
             if (chat.get('type') === _converse.PRIVATE_CHAT_TYPE) {
                 fetchNewestMessages(chat);
             }
         });
 
         api.listen.on('afterMessagesFetched', chat => {
-            // XXX: We don't want to query MAM every time this is triggered
-            // since it's not necessary when the chat is restored from cache.
-            // (given that BOSH or SMACKS will ensure that you get messages
-            // sent during the reload).
-            // With MUCs we can listen for `enteredNewRoom`.
-            if (chat.get('type') === _converse.PRIVATE_CHAT_TYPE && !_converse.connection.restored) {
+            if (chat.get('type') === _converse.PRIVATE_CHAT_TYPE) {
                 fetchNewestMessages(chat);
             }
         });