media: Opus support for WebM in Media Source

media/base/audio_decoder_config.h

Index: media/base/audio_decoder_config.h
diff --git a/media/base/audio_decoder_config.h b/media/base/audio_decoder_config.h
index 1c61e70c3adba554c50a83d8f63e6f4208fc0296..a17d2215b97a3502b414a3de04dc2b549ff7b730 100644
--- a/media/base/audio_decoder_config.h
+++ b/media/base/audio_decoder_config.h
@@ -8,6 +8,7 @@
 #include <vector>
 
 #include "base/basictypes.h"
+#include "base/time/time.h"
 #include "media/base/channel_layout.h"
 #include "media/base/media_export.h"
 #include "media/base/sample_format.h"
@@ -63,7 +64,9 @@ class MEDIA_EXPORT AudioDecoderConfig {
   void Initialize(AudioCodec codec, SampleFormat sample_format,
                   ChannelLayout channel_layout, int samples_per_second,
                   const uint8* extra_data, size_t extra_data_size,
-                  bool is_encrypted, bool record_stats);
+                  bool is_encrypted, bool record_stats,
+                  base::TimeDelta seek_preroll,
+                  base::TimeDelta codec_delay);
 
   // Returns true if this object has appropriate configuration values, false
   // otherwise.
@@ -80,6 +83,8 @@ class MEDIA_EXPORT AudioDecoderConfig {
   int samples_per_second() const { return samples_per_second_; }
   SampleFormat sample_format() const { return sample_format_; }
   int bytes_per_frame() const { return bytes_per_frame_; }
+  base::TimeDelta seek_preroll() const { return seek_preroll_; }
+  base::TimeDelta codec_delay() const { return codec_delay_; }
 
   // Optional byte data required to initialize audio decoders such as Vorbis
   // codebooks.
@@ -103,6 +108,15 @@ class MEDIA_EXPORT AudioDecoderConfig {
   std::vector<uint8> extra_data_;
   bool is_encrypted_;
 
+  // |seek_preroll_| is the duration of the data that the decoder must decode
+  // before the decoded data is valid.
+  base::TimeDelta seek_preroll_;
+
+  // |codec_delay_| is the overall delay overhead added by the codec while
+  // encoding. This value should be subtracted from each block's timestamp to
+  // get the actual timestamp.
+  base::TimeDelta codec_delay_;
+
   // Not using DISALLOW_COPY_AND_ASSIGN here intentionally to allow the compiler
   // generated copy constructor and assignment operator. Since the extra data is
   // typically small, the performance impact is minimal.