fix(GUM): Don't fail when a track is muted.

JitsiTrackError.js

     = 'Track has been already disposed';
 TRACK_ERROR_TO_MESSAGE_MAP[JitsiTrackErrors.TRACK_NO_STREAM_FOUND]
     = 'Track does not have an associated Media Stream';
-TRACK_ERROR_TO_MESSAGE_MAP[JitsiTrackErrors.NO_DATA_FROM_SOURCE]
-    = 'The track has stopped receiving data from it\'s source';
-
 
 // FIXME: Using prototype inheritance because otherwise instanceof is not
 // working properly (see https://github.com/babel/babel/issues/3083)

JitsiTrackErrors.js

  * by a webcam.
  */
 export const UNSUPPORTED_RESOLUTION = 'gum.unsupported_resolution';
-
-/**
- * Indicates that the track is no receiving any data without reason(the
- * stream was stopped, etc)
- */
-export const NO_DATA_FROM_SOURCE = 'track.no_data_from_source';

modules/RTC/RTC.js

 import GlobalOnErrorHandler from '../util/GlobalOnErrorHandler';
 import * as JitsiConferenceEvents from '../../JitsiConferenceEvents';
 import JitsiLocalTrack from './JitsiLocalTrack';
-import JitsiTrackError from '../../JitsiTrackError';
-import * as JitsiTrackErrors from '../../JitsiTrackErrors';
 import Listenable from '../util/Listenable';
 import { safeCounterIncrement } from '../util/MathUtil';
 import * as MediaType from '../../service/RTC/MediaType';
             ? RTCUtils.newObtainAudioAndVideoPermissions(options)
             : RTCUtils.obtainAudioAndVideoPermissions(options);
 
-        return obtainMediaPromise.then(
-            tracksInfo => {
-                const tracks = usesNewGumFlow
-                    ? _newCreateLocalTracks(tracksInfo)
-                    : createLocalTracks(tracksInfo, options);
-
-                return tracks.some(track => !track._isReceivingData())
-                    ? Promise.reject(
-                        new JitsiTrackError(
-                            JitsiTrackErrors.NO_DATA_FROM_SOURCE))
-                    : tracks;
-            });
+        return obtainMediaPromise.then(tracksInfo => {
+            if (usesNewGumFlow) {
+                return _newCreateLocalTracks(tracksInfo);
+            }
+
+            return createLocalTracks(tracksInfo, options);
+        });
     }
 
     /**