Update MediaStreamTrack::Stop to latest draft.

content/renderer/media/webrtc/media_stream_remote_video_source.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/media/webrtc/media_stream_remote_video_source.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "content/renderer/media/native_handle_impl.h"
 #include "media/base/video_frame.h"
@@ skipping 29 matching lines @@
 }
 
 void MediaStreamRemoteVideoSource::StartSourceImpl(
     const media::VideoCaptureParams& params) {
   DCHECK(message_loop_proxy_->BelongsToCurrentThread());
   OnStartDone(true);
 }
 
 void MediaStreamRemoteVideoSource::StopSourceImpl() {
   DCHECK(message_loop_proxy_->BelongsToCurrentThread());
-  remote_track_->RemoveRenderer(this);
-  remote_track_->UnregisterObserver(this);
+  if (state() != MediaStreamVideoSource::ENDED) {
+    remote_track_->RemoveRenderer(this);
+    remote_track_->UnregisterObserver(this);
+  }
 }
 
 webrtc::VideoSourceInterface* MediaStreamRemoteVideoSource::GetAdapter() {
   DCHECK(message_loop_proxy_->BelongsToCurrentThread());
   return remote_track_->GetSource();
 }
 
 void MediaStreamRemoteVideoSource::SetSize(int width, int height) {
 }
 
@@ skipping 86 matching lines @@
 }
 
 void MediaStreamRemoteVideoSource::DoRenderFrameOnMainThread(
     scoped_refptr<media::VideoFrame> video_frame) {
   DCHECK(message_loop_proxy_->BelongsToCurrentThread());
   if (state() == STARTED)
     DeliverVideoFrame(video_frame);
 }
 
 }  // namespace content