Propagate MediaStreamSource state to video tracks the same way as audio.

webrtc/api/mediastreamtrack.h

 /*
  *  Copyright 2011 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. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 30 matching lines @@
   virtual bool set_state(MediaStreamTrackInterface::TrackState new_state) {
     bool fire_on_change = (state_ != new_state);
     state_ = new_state;
     if (fire_on_change)
       Notifier<T>::FireOnChanged();
     return true;
   }
 
  protected:
   explicit MediaStreamTrack(const std::string& id)
-      : enabled_(true),
-        id_(id),
-        state_(MediaStreamTrackInterface::kInitializing) {
-  }
+      : enabled_(true), id_(id), state_(MediaStreamTrackInterface::kLive) {}
 
  private:
   bool enabled_;
   std::string id_;
   MediaStreamTrackInterface::TrackState state_;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_API_MEDIASTREAMTRACK_H_