Notify the track before source provider goes away.

content/renderer/media/media_stream_dependency_factory.cc

 // Copyright (c) 2012 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/media_stream_dependency_factory.h"
 
 #include <vector>
 
 #include "base/command_line.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 549 matching lines @@
   // TODO(xians): Merge |source| to the capturer(). We can't do this today
   // because only one capturer() is supported while one |source| is created
   // for each audio track.
   scoped_ptr<WebRtcLocalAudioTrack> audio_track(
       new WebRtcLocalAudioTrack(adapter,
                                 source_data->GetAudioCapturer(),
                                 webaudio_source));
 
   StartLocalAudioTrack(audio_track.get());
 
-  // Pass the pointer of the source provider to the blink audio track.
+  // Pass the ownership of the native local audio track to the blink track.
   blink::WebMediaStreamTrack writable_track = track;
-  writable_track.setSourceProvider(audio_track->audio_source_provider());
-
-  // Pass the ownership of the native local audio track to the blink track.
   writable_track.setExtraData(audio_track.release());
 }
 
 void MediaStreamDependencyFactory::StartLocalAudioTrack(
     WebRtcLocalAudioTrack* audio_track) {
   // Add the WebRtcAudioDevice as the sink to the local audio track.
   // TODO(xians): Implement a PeerConnection sink adapter and remove this
   // AddSink() call.
   audio_track->AddSink(GetWebRtcAudioDevice());
   // Start the audio track. This will hook the |audio_track| to the capturer
@@ skipping 207 matching lines @@
 }
 
 void MediaStreamDependencyFactory::EnsureWebRtcAudioDeviceImpl() {
   if (audio_device_)
     return;
 
   audio_device_ = new WebRtcAudioDeviceImpl();
 }
 
 }  // namespace content