ref(ChatRoom): move emit remote stream added

There's no reason to involve the ChatRoom directly into the generation
of remote stream added event. It merely provides some info carried in
the presence about muted state etc.

modules/xmpp/ChatRoom.js

         this.sendPresence();
     }
 
-    remoteTrackAdded (data) {
+    /**
+     * An object that carries the info portion about specific media type
+     * advertised by participant in MUC presence.
+     * @typedef {Object} MediaPresenceInfo
+     * @property {boolean} muted indicates if the media is currently muted
+     * @property {VideoType|undefined} videoType the type of the video if applicable
+     */
+    /**
+     * Obtains the info about given media advertised in the MUC presence of
+     * the participant identified by the given MUC JID.
+     * @param {string} peerjid the MUC jid of the participant for whom
+     * {@link MediaPresenceInfo} will be obtained.
+     * @param {MediaType} mediaType the type of the media for which presence
+     * info will be obtained.
+     * @return {MediaPresenceInfo} presenceInfo an object with media presence
+     * info or <tt>null</tt> either if there is no presence available for given
+     * JID or if the media type given is invalid.
+     */
+    getMediaPresenceInfo (peerjid, mediaType) {
         // Will figure out current muted status by looking up owner's presence
-        var pres = this.lastPresences[data.owner];
-        if(pres) {
-            var mediaType = data.mediaType;
-            var mutedNode = null;
-            if (mediaType === MediaType.AUDIO) {
-                mutedNode = filterNodeFromPresenceJSON(pres, "audiomuted");
-            } else if (mediaType === MediaType.VIDEO) {
-                mutedNode = filterNodeFromPresenceJSON(pres, "videomuted");
-                var videoTypeNode = filterNodeFromPresenceJSON(pres, "videoType");
-                if(videoTypeNode
-                    && videoTypeNode.length > 0
-                    && videoTypeNode[0])
-                    data.videoType = videoTypeNode[0]["value"];
-            } else {
-                logger.warn("Unsupported media type: " + mediaType);
-                data.muted = null;
-            }
-
-            if (mutedNode) {
-                data.muted = mutedNode.length > 0 &&
-                             mutedNode[0] &&
-                             mutedNode[0]["value"] === "true";
+        const pres = this.lastPresences[peerjid];
+        if (!pres) {
+            // No presence available
+            return null;
+        }
+        const data = {
+            muted: false, // unmuted by default
+            videoType: undefined // no video type by default
+        };
+        let mutedNode = null;
+
+        if (mediaType === MediaType.AUDIO) {
+            mutedNode = filterNodeFromPresenceJSON(pres, "audiomuted");
+        } else if (mediaType === MediaType.VIDEO) {
+            mutedNode = filterNodeFromPresenceJSON(pres, "videomuted");
+            let videoTypeNode = filterNodeFromPresenceJSON(pres, "videoType");
+
+            if(videoTypeNode.length > 0) {
+                data.videoType = videoTypeNode[0]["value"];
             }
+        } else {
+            logger.error("Unsupported media type: " + mediaType);
+            return null;
         }
 
-        this.eventEmitter.emit(XMPPEvents.REMOTE_TRACK_ADDED, data);
+        data.muted = mutedNode.length > 0 && mutedNode[0]["value"] === "true";
+
+        return data;
     }
 
     /**

modules/xmpp/JingleSessionPC.js

         track: track,
         mediaType: track.kind, /* 'audio' or 'video' */
         owner: undefined, /* to be determined below */
-        muted: null /* will be set in the ChatRoom */
+        muted: null /* will be obtained from MUC presence */,
+        videoType: undefined /* obtained from MUC presence if video */
     };
     try{
         // look up an associated JID for a stream id
         }
         jitsiTrackAddedEvent.ssrc = thessrc;
 
-        this.room.remoteTrackAdded(jitsiTrackAddedEvent);
+        const streamPresenceInfo
+            = this.room.getMediaPresenceInfo(
+                    jitsiTrackAddedEvent.owner,
+                    jitsiTrackAddedEvent.mediaType);
+
+        if (streamPresenceInfo) {
+            jitsiTrackAddedEvent.muted = streamPresenceInfo.muted;
+            jitsiTrackAddedEvent.videoType = streamPresenceInfo.videoType;
+        } else {
+            logger.warn(
+                "No presence info available for: "
+                    + jitsiTrackAddedEvent.owner);
+        }
+
+        this.room.eventEmitter.emit(
+            XMPPEvents.REMOTE_TRACK_ADDED, jitsiTrackAddedEvent);
     } catch (error) {
         GlobalOnErrorHandler.callErrorHandler(error);
     }