Replace the guts of AudioRendererBase with calls to scaling algorithm.

media/filters/null_audio_renderer.h

 // Copyright (c) 2009 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.
 
 #ifndef MEDIA_FILTERS_NULL_AUDIO_RENDERER_H_
 #define MEDIA_FILTERS_NULL_AUDIO_RENDERER_H_
 
 // NullAudioRenderer effectively uses an extra thread to "throw away" the
 // audio data at a rate resembling normal playback speed.  It's just like
 // decoding to /dev/null!
@@ skipping 21 matching lines @@
 class NullAudioRenderer : public AudioRendererBase, PlatformThread::Delegate {
  public:
   // FilterFactory provider.
   static FilterFactory* CreateFilterFactory() {
     return new FilterFactoryImpl0<NullAudioRenderer>();
   }
 
   // Compatible with any audio/x-uncompressed MediaFormat.
   static bool IsMediaFormatSupported(const MediaFormat& media_format);
 
-  // MediaFilter implementation.
-  virtual void SetPlaybackRate(float playback_rate);
-
   // AudioRenderer implementation.
   virtual void SetVolume(float volume);
 
   // PlatformThread::Delegate implementation.
   virtual void ThreadMain();
 
  protected:
   // Only allow a factory to create this class.
   friend class FilterFactoryImpl0<NullAudioRenderer>;
   NullAudioRenderer();
   virtual ~NullAudioRenderer();
 
   // AudioRendererBase implementation.
   virtual bool OnInitialize(const MediaFormat& media_format);
   virtual void OnStop();
 
  private:
-  // Current playback rate.
-  float playback_rate_;
-
   // A number to convert bytes written in FillBuffer to milliseconds based on
   // the audio format.  Calculated in OnInitialize by looking at the decoder's
   // MediaFormat.
   size_t bytes_per_millisecond_;
 
   // A buffer passed to FillBuffer to advance playback.
   scoped_ptr<uint8> buffer_;
   size_t buffer_size_;
 
   // Separate thread used to throw away data.
   PlatformThreadHandle thread_;
 
   // Shutdown flag.
   bool shutdown_;
 
   DISALLOW_COPY_AND_ASSIGN(NullAudioRenderer);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_NULL_AUDIO_RENDERER_H_