Refactor audio and video decoder status into common file.

media/filters/decoder_stream.h

Index: media/filters/decoder_stream.h
diff --git a/media/filters/decoder_stream.h b/media/filters/decoder_stream.h
index 3af3d752b1b3b785e8f1e0ed9c4a6a7513fc9a87..a7f084fa3f6f806caff60e210708abe6a86ec85a 100644
--- a/media/filters/decoder_stream.h
+++ b/media/filters/decoder_stream.h
@@ -39,7 +39,6 @@ class MEDIA_EXPORT DecoderStream {
   typedef DecoderStreamTraits<StreamType> StreamTraits;
   typedef typename StreamTraits::DecoderType Decoder;
   typedef typename StreamTraits::OutputType Output;
-  typedef typename Decoder::Status DecoderStatus;
 
   enum Status {
     OK,  // Everything went as planned.
@@ -156,7 +155,7 @@ class MEDIA_EXPORT DecoderStream {
   void FlushDecoder();
 
   // Callback for Decoder::Decode().
-  void OnDecodeDone(int buffer_size, bool end_of_stream, DecoderStatus status);
+  void OnDecodeDone(int buffer_size, bool end_of_stream, DecodeStatus status);
 
   // Output callback passed to Decoder::Initialize().
   void OnDecodeOutputReady(const scoped_refptr<Output>& output);