Add audio playback (all platforms) to cast_receiver_app.

media/cast/test/utility/in_process_receiver.h

Index: media/cast/test/utility/in_process_receiver.h
diff --git a/media/cast/test/utility/in_process_receiver.h b/media/cast/test/utility/in_process_receiver.h
index d50514fb638ac2dfba7a4c08767611894b4392c1..06a798eb4cf72ac5ef7e5c55f48428775c443098 100644
--- a/media/cast/test/utility/in_process_receiver.h
+++ b/media/cast/test/utility/in_process_receiver.h
@@ -49,7 +49,6 @@ class InProcessReceiver {
                     const AudioReceiverConfig& audio_config,
                     const VideoReceiverConfig& video_config);
 
-  // Must be destroyed on the cast MAIN thread.  See DestroySoon().
   virtual ~InProcessReceiver();
 
   // Convenience accessors.
@@ -59,17 +58,11 @@ class InProcessReceiver {
 
   // Begin delivering any received audio/video frames to the OnXXXFrame()
   // methods.
-  void Start();
-
-  // Schedules destruction on the cast MAIN thread.  Any external references to
-  // the InProcessReceiver instance become invalid.
-  // Deprecated: Use Stop instead.
-  // TODO(hubbe): Remove this function and change callers to use Stop.
-  void DestroySoon();
+  virtual void Start();
 
   // Destroy the sub-compontents of this class.
   // After this call, it is safe to destroy this object on any thread.
-  void Stop();
+  virtual void Stop();
 
  protected:
   // To be implemented by subclasses.  These are called on the Cast MAIN thread
@@ -109,9 +102,6 @@ class InProcessReceiver {
   void PullNextAudioFrame();
   void PullNextVideoFrame();
 
-  // Invoked just before the destruction of |receiver| on the cast MAIN thread.
-  static void WillDestroyReceiver(InProcessReceiver* receiver);
-
   const scoped_refptr<CastEnvironment> cast_environment_;
   const net::IPEndPoint local_end_point_;
   const net::IPEndPoint remote_end_point_;