Add support for unmixed audio from remote WebRTC remote tracks.

content/renderer/media/remote_media_stream_impl.cc

 // Copyright (c) 2013 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/remote_media_stream_impl.h"
 
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
@@ skipping 213 matching lines @@
   unregistered_ = true;
 #endif
   observed_track()->UnregisterObserver(this);
 }
 
 void RemoteAudioTrackAdapter::InitializeWebkitAudioTrack() {
   scoped_ptr<MediaStreamRemoteAudioTrack> media_stream_track(
       new MediaStreamRemoteAudioTrack(observed_track().get()));
   InitializeWebkitTrack(blink::WebMediaStreamSource::TypeAudio);
   webkit_track()->setExtraData(media_stream_track.release());
+  // TODO(tommi): Set the remote audio track extra data.

[perkj_chrome, 2015/12/11 12:31:38]

audio source

[tommi (sloooow) - chröme, 2015/12/11 15:36:51]

Done.

+  // webkit_track()->source().setExtraData(...);
 }
 
 void RemoteAudioTrackAdapter::OnChanged() {
   main_thread_->PostTask(FROM_HERE,
       base::Bind(&RemoteAudioTrackAdapter::OnChangedOnMainThread,
           this, observed_track()->state()));
 }
 
 void RemoteAudioTrackAdapter::OnChangedOnMainThread(
     webrtc::MediaStreamTrackInterface::TrackState state) {
@@ skipping 169 matching lines @@
   // Unregister all the audio track observers that were not used.
   // We need to do this before destruction since the observers can't unregister
   // from within the dtor due to a race.
   for (auto& track : *audio_tracks.get()) {
     if (track.get())
       track->Unregister();
   }
 }
 
 }  // namespace content