Introduce AudioDecoderConfig to migrate away from GetAVStream().

media/base/filters.h

Index: media/base/filters.h
diff --git a/media/base/filters.h b/media/base/filters.h
index d45ed2afa2fb00653ba10562ffa625c8d3dbf473..a24572a92a0073752ae734df9cbfd624f20fa60a 100644
--- a/media/base/filters.h
+++ b/media/base/filters.h
@@ -40,6 +40,7 @@ struct AVStream;
 
 namespace media {
 
+class AudioDecoderConfig;
 class Buffer;
 class Decoder;
 class DemuxerStream;
@@ -179,6 +180,10 @@ class MEDIA_EXPORT DemuxerStream
   // Returns an |AVStream*| if supported, or NULL.

[Ami GONE FROM CHROMIUM, 2011/09/12 20:54:21]

Is there a chance to remove this at the same time?

[scherkus (not reviewing), 2011/09/19 21:19:45]

Not yet :\

[Ami GONE FROM CHROMIUM, 2011/09/29 18:16:35]

How about now that AdaptiveDemuxer is dead? :)

   virtual AVStream* GetAVStream();
 
+  // Returns a weak reference to the audio decoder configuration if present,

[Ami GONE FROM CHROMIUM, 2011/09/12 20:54:21]

"weak reference"??

+  // NULL otherwise.
+  virtual AudioDecoderConfig* audio_decoder_config() = 0;
+
   // Returns the type of stream.
   virtual Type type() = 0;