Move a couple calls to update VideoLayout into the redux update flow (#3173)

* ref(video-layout): move middleware for TRACK_ADDED

* ref(video-layout): call mucJoined when redux knowns of conference join

modules/UI/UI.js

@@ -267,16 +267,6 @@ UI.initConference = function() {
     followMeHandler = new FollowMe(APP.conference, UI);
 };
 
-UI.mucJoined = function() {
-    VideoLayout.mucJoined();
-
-    // Update local video now that a conference is joined a user ID should be
-    // set.
-    UI.changeDisplayName(
-        'localVideoContainer',
-        APP.conference.getLocalDisplayName());
-};
-
 /** *
  * Handler for toggling filmstrip
  */
@@ -415,13 +405,6 @@ UI.addLocalStream = track => {
     }
 };
 
-
-/**
- * Show remote stream on UI.
- * @param {JitsiTrack} track stream to show
- */
-UI.addRemoteStream = track => VideoLayout.onRemoteStreamAdded(track);
-
 /**
  * Removed remote stream from UI.
  * @param {JitsiTrack} track stream to remove