Associate audio streams with their source/destination RenderView.

content/renderer/media/audio_renderer_mixer_manager.h

Index: content/renderer/media/audio_renderer_mixer_manager.h
diff --git a/content/renderer/media/audio_renderer_mixer_manager.h b/content/renderer/media/audio_renderer_mixer_manager.h
index dba3ba82df7aa691f13ed034ce3e2f21eba102f6..6c6e0e871e6f32d86898b50d04d7af95327c4195 100644
--- a/content/renderer/media/audio_renderer_mixer_manager.h
+++ b/content/renderer/media/audio_renderer_mixer_manager.h
@@ -14,6 +14,7 @@
 namespace media {
 class AudioRendererMixer;
 class AudioRendererMixerInput;
+class AudioRendererSink;
 }
 
 namespace content {
@@ -45,6 +46,9 @@ class CONTENT_EXPORT AudioRendererMixerManager {
  private:
   friend class AudioRendererMixerManagerTest;
 
+  // Overrides the AudioRendererSink implementation for unit testing.
+  void SetAudioRendererSinkForTesting(media::AudioRendererSink* sink);
+
   // Returns a mixer instance based on AudioParameters; an existing one if one
   // with the provided AudioParameters exists or a new one if not.
   media::AudioRendererMixer* GetMixer(const media::AudioParameters& params);
@@ -71,6 +75,8 @@ class CONTENT_EXPORT AudioRendererMixerManager {
   int hardware_sample_rate_;
   int hardware_buffer_size_;
 
+  media::AudioRendererSink* sink_for_testing_;
+
   DISALLOW_COPY_AND_ASSIGN(AudioRendererMixerManager);
 };