Miscellaneous header file cleanup for src/media.

media/ffmpeg/ffmpeg_common.h

 // Copyright (c) 2011 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_FFMPEG_FFMPEG_COMMON_H_
 #define MEDIA_FFMPEG_FFMPEG_COMMON_H_
 
 // Used for FFmpeg error codes.
 #include <cerrno>
 
 #include "base/compiler_specific.h"
-#include "base/memory/singleton.h"
 #include "base/time.h"
-#include "media/base/audio_decoder_config.h"
 #include "media/base/channel_layout.h"
 #include "media/base/media_export.h"
-#include "media/video/video_decode_engine.h"
-#include "ui/gfx/size.h"
+#include "media/base/video_frame.h"
 
 // Include FFmpeg header files.
 extern "C" {
 // Temporarily disable possible loss of data warning.
 // TODO(scherkus): fix and upstream the compiler warnings.
 MSVC_PUSH_DISABLE_WARNING(4244);
 #include <libavcodec/avcodec.h>
 #include <libavformat/avformat.h>
 #include <libavformat/avio.h>
 #include <libavutil/avutil.h>
 #include <libavutil/log.h>
 MSVC_POP_WARNING();
 }  // extern "C"
 
 namespace media {
 
+class AudioDecoderConfig;
+class VideoDecoderConfig;
+
 // Wraps FFmpeg's av_free() in a class that can be passed as a template argument
 // to scoped_ptr_malloc.
 class ScopedPtrAVFree {
  public:
   inline void operator()(void* x) const {
     av_free(x);
   }
 };
 
 // This assumes that the AVPacket being captured was allocated outside of
@@ skipping 52 matching lines @@
 // |config|.
 base::TimeDelta GetFrameDuration(const VideoDecoderConfig& config);
 
 // Closes & destroys all AVStreams in the context and then closes &
 // destroys the AVFormatContext.
 void DestroyAVFormatContext(AVFormatContext* format_context);
 
 }  // namespace media
 
 #endif  // MEDIA_FFMPEG_FFMPEG_COMMON_H_