Refactor AudioRendererMixer to be more generic.

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 dd2575bc73e8b4a976e612a8cf0ee0785d4e2790..10901c1cf22123708b268de344b5837be51260a5 100644
--- a/content/renderer/media/audio_renderer_mixer_manager.h
+++ b/content/renderer/media/audio_renderer_mixer_manager.h
@@ -50,6 +50,17 @@ class CONTENT_EXPORT AudioRendererMixerManager {
   // the returned input.
   media::AudioRendererMixerInput* CreateInput(int source_render_view_id);
 
+  // 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(int source_render_view_id,
+                                      const media::AudioParameters& params);
+
+  // Remove a mixer instance given a mixer if the only other reference is held
+  // by AudioRendererMixerManager.  Every AudioRendererMixer owner must call
+  // this method when it's done with a mixer.
+  void RemoveMixer(int source_render_view_id,
+                   const media::AudioParameters& params);
+
  private:
   friend class AudioRendererMixerManagerTest;
 
@@ -69,17 +80,6 @@ class CONTENT_EXPORT AudioRendererMixerManager {
   // 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(int source_render_view_id,
-                                      const media::AudioParameters& params);
-
-  // Remove a mixer instance given a mixer if the only other reference is held
-  // by AudioRendererMixerManager.  Every AudioRendererMixer owner must call
-  // this method when it's done with a mixer.
-  void RemoveMixer(int source_render_view_id,
-                   const media::AudioParameters& params);
-
   // Active mixers.
   AudioRendererMixerMap mixers_;
   base::Lock mixers_lock_;