Introduce AudioDecoderConfig to migrate away from GetAVStream().

media/ffmpeg/ffmpeg_common.h

Index: media/ffmpeg/ffmpeg_common.h
diff --git a/media/ffmpeg/ffmpeg_common.h b/media/ffmpeg/ffmpeg_common.h
index dec47dfaa7910ddeaa73dfd979652dc8cbbb55b0..5039b784d56e177340c44001d1c625b12b45cfb4 100644
--- a/media/ffmpeg/ffmpeg_common.h
+++ b/media/ffmpeg/ffmpeg_common.h
@@ -11,6 +11,7 @@
 #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"
@@ -65,6 +66,12 @@ MEDIA_EXPORT base::TimeDelta ConvertFromTimeBase(const AVRational& time_base,
 MEDIA_EXPORT int64 ConvertToTimeBase(const AVRational& time_base,
                                      const base::TimeDelta& timestamp);
 
+AudioDecoderConfig* AVCodecContextToAudioDecoderConfig(

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

Returning a new'd struct isn't very google-c++-stylish.
Any reason not to use the style in the next method, or just return a copy?

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

Done.

+    AVCodecContext* codec_context);
+void AudioDecoderConfigToAVCodecContext(
+    const AudioDecoderConfig* config,
+    AVCodecContext* codec_context);
+
 VideoCodec CodecIDToVideoCodec(CodecID codec_id);
 CodecID VideoCodecToCodecID(VideoCodec video_codec);