Revert 276939 "Decouple IPC::MessageFilter from IPC::Channel"

content/renderer/media/audio_message_filter.h

Index: content/renderer/media/audio_message_filter.h
===================================================================
--- content/renderer/media/audio_message_filter.h	(revision 278168)
+++ content/renderer/media/audio_message_filter.h	(working copy)
@@ -65,12 +65,12 @@
   // stream_id and the source render_view_id.
   class AudioOutputIPCImpl;
 
-  // Sends an IPC message using |sender_|.
+  // Sends an IPC message using |channel_|.
   void Send(IPC::Message* message);
 
   // IPC::MessageFilter override. Called on |io_message_loop|.
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
-  virtual void OnFilterAdded(IPC::Sender* sender) OVERRIDE;
+  virtual void OnFilterAdded(IPC::Channel* channel) OVERRIDE;
   virtual void OnFilterRemoved() OVERRIDE;
   virtual void OnChannelClosing() OVERRIDE;
 
@@ -92,8 +92,8 @@
   void OnOutputDeviceChanged(int stream_id, int new_buffer_size,
                              int new_sample_rate);
 
-  // IPC sender for Send(); must only be accesed on |io_message_loop_|.
-  IPC::Sender* sender_;
+  // IPC channel for Send(); must only be accesed on |io_message_loop_|.
+  IPC::Channel* channel_;
 
   // A map of stream ids to delegates; must only be accessed on
   // |io_message_loop_|.