Provide a Chrome-owned buffer to FFmpeg for video decoding, instead of

media/filters/ffmpeg_video_decoder.h

Index: media/filters/ffmpeg_video_decoder.h
===================================================================
--- media/filters/ffmpeg_video_decoder.h	(revision 142616)
+++ media/filters/ffmpeg_video_decoder.h	(working copy)
@@ -38,6 +38,11 @@
   // encountered.
   void set_decryptor(AesDecryptor* decryptor);
 
+  // Callback called from within FFmpeg to allocate a buffer based on
+  // the dimensions of |codec_context|. See AVCodecContext.get_buffer
+  // documentation inside FFmpeg.
+  int GetVideoBuffer(AVCodecContext *codec_context, AVFrame* frame);
+
  protected:
   virtual ~FFmpegVideoDecoder();
 
@@ -71,10 +76,6 @@
   // Reset decoder and call |reset_cb_|.
   void DoReset();
 
-  // Allocates a video frame based on the current format and dimensions based on
-  // the current state of |codec_context_|.
-  scoped_refptr<VideoFrame> AllocateVideoFrame();
-
   // This is !is_null() iff Initialize() hasn't been called.
   base::Callback<MessageLoop*()> message_loop_factory_cb_;