media: Cleanup class/struct forward declarations

media/base/audio_decoder.h

 // Copyright (c) 2012 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_BASE_AUDIO_DECODER_H_
 #define MEDIA_BASE_AUDIO_DECODER_H_
 
 #include <string>
 
 #include "base/callback.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "media/base/audio_decoder_config.h"
 #include "media/base/channel_layout.h"
 #include "media/base/decode_status.h"
 #include "media/base/decoder_buffer.h"
 #include "media/base/media_export.h"
 #include "media/base/pipeline_status.h"
 
 namespace media {
 
 class AudioBuffer;
 class CdmContext;
-class DemuxerStream;
 
 class MEDIA_EXPORT AudioDecoder {
  public:
   // Callback for VideoDecoder initialization.
   typedef base::Callback<void(bool success)> InitCB;
 
   // Callback for AudioDecoder to return a decoded frame whenever it becomes
   // available. Only non-EOS frames should be returned via this callback.
   typedef base::Callback<void(const scoped_refptr<AudioBuffer>&)> OutputCB;
 
@@ skipping 45 matching lines @@
   // Returns true if the decoder needs bitstream conversion before decoding.
   virtual bool NeedsBitstreamConversion() const;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(AudioDecoder);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_AUDIO_DECODER_H_