FOR TESTING ONLY: Enable ffvp9 inside of Chrome.

media/filters/ffmpeg_video_decoder.h

Index: media/filters/ffmpeg_video_decoder.h
diff --git a/media/filters/ffmpeg_video_decoder.h b/media/filters/ffmpeg_video_decoder.h
index 8acc4c8e02d4f5afd1c07477cab41b67a10253c1..24298e8f1521ed620265ebfed96049a301163bc8 100644
--- a/media/filters/ffmpeg_video_decoder.h
+++ b/media/filters/ffmpeg_video_decoder.h
@@ -72,6 +72,11 @@ class MEDIA_EXPORT FFmpegVideoDecoder : public VideoDecoder {
   // and resets them to NULL.
   void ReleaseFFmpegResources();
 
+  int ParseVP9Packet(uint8_t** out_data,
+                     int* out_size,
+                     uint8_t* data,
+                     int size);
+
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
 
   DecoderState state_;
@@ -88,6 +93,12 @@ class MEDIA_EXPORT FFmpegVideoDecoder : public VideoDecoder {
 
   bool decode_nalus_;
 
+  struct VP9ParseContext {
+    int n_frames;
+    int size[8];
+  };
+  VP9ParseContext parse_context_;
+
   DISALLOW_COPY_AND_ASSIGN(FFmpegVideoDecoder);
 };