MediaStream audio: Refactor 3 separate "glue" implementations into one.

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 <stddef.h>
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/thread_task_runner_handle.h"
 #include "content/renderer/media/media_stream.h"
 #include "content/renderer/media/media_stream_track.h"
 #include "content/renderer/media/media_stream_video_track.h"
-#include "content/renderer/media/webrtc/media_stream_remote_audio_track.h"
 #include "content/renderer/media/webrtc/media_stream_remote_video_source.h"
 #include "content/renderer/media/webrtc/peer_connection_dependency_factory.h"
+#include "content/renderer/media/webrtc/peer_connection_remote_audio_source.h"
 #include "content/renderer/media/webrtc/track_observer.h"
 #include "third_party/WebKit/public/platform/WebMediaStreamSource.h"
 #include "third_party/WebKit/public/platform/WebMediaStreamTrack.h"
 #include "third_party/WebKit/public/platform/WebString.h"
 
 namespace content {
 namespace {
 
 template <typename WebRtcTrackVector, typename AdapterType>
 void CreateAdaptersForTracks(
@@ skipping 198 matching lines @@
 #if DCHECK_IS_ON()
   DCHECK(!unregistered_);
   unregistered_ = true;
 #endif
   observed_track()->UnregisterObserver(this);
 }
 
 void RemoteAudioTrackAdapter::InitializeWebkitAudioTrack() {
   InitializeWebkitTrack(blink::WebMediaStreamSource::TypeAudio);
 
-  webkit_track()->source().setExtraData(
-      new MediaStreamRemoteAudioSource(observed_track().get()));
-  webkit_track()->setExtraData(
-      new MediaStreamRemoteAudioTrack(
-          webkit_track()->source(), webkit_track()->isEnabled()));
+  MediaStreamAudioSource* const source =
+      new PeerConnectionRemoteAudioSource(observed_track().get());
+  webkit_track()->source().setExtraData(source);  // Takes ownership.
+  source->ConnectToTrack(*(webkit_track()));
 }
 
 void RemoteAudioTrackAdapter::OnChanged() {
   main_thread_->PostTask(FROM_HERE,
       base::Bind(&RemoteAudioTrackAdapter::OnChangedOnMainThread,
           this, observed_track()->state()));
 }
 
 void RemoteAudioTrackAdapter::OnChangedOnMainThread(
     webrtc::MediaStreamTrackInterface::TrackState state) {
@@ skipping 167 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