Modify MojoRendererService to host a RendererImpl.

media/mojo/interfaces/media_renderer.mojom

 // Copyright 2014 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.
 
 import "media/mojo/interfaces/demuxer_stream.mojom"
 import "media/mojo/interfaces/media_types.mojom"
 
 module mojo {
 
 [Client=MediaRendererClient]
 interface MediaRenderer {
   // Initializes the Renderer with |stream|, calling back upon completion.
   // NOTE: If an error occurs, MediaRendererClient::OnError() will be called
   // before the callback is executed.
   Initialize(DemuxerStream stream) => ();
 
   // Discards any buffered data, executing callback when completed.
   // NOTE: If an error occurs, MediaRendererClient::OnError() can be called
   // before the callback is executed.
   Flush() => ();
 
   // Starts rendering from |time_usec|.
   StartPlayingFrom(int64 time_usec);
 
   // Updates the current playback rate. The default playback rate should be 1.
   SetPlaybackRate(float playback_rate);
-  
+
   // Sets the output volume. The default volume should be 1.
   SetVolume(float volume);
 };
 
 interface MediaRendererClient {
   // Called to report media time advancement by |time_usec|.
   // |time_usec| and |max_time_usec| can be used to interpolate time between
   // calls to OnTimeUpdate().
   // |max_time_usec| is typically the media timestamp of the last audio frame
   //     buffered by the audio hardware.
   // |max_time_usec| must be greater or equal to |time_usec|.
   OnTimeUpdate(int64 time_usec, int64 max_time_usec);
 
   // Called to report buffering state changes, see media_types.mojom.
   OnBufferingStateChange(BufferingState state);
 
   // Executed when rendering has reached the end of stream.
   OnEnded();
 
   // Executed if any error was encountered during decode or rendering. If
   // this error happens during an operation that has a completion callback,
   // OnError() will be called before firing the completion callback.
   OnError();
 };
 
 }  // module mojo