Unify media track info reporting on a demuxer level

media/base/demuxer.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_BASE_DEMUXER_H_
 #define MEDIA_BASE_DEMUXER_H_
 
 #include <stdint.h>
 
 #include <vector>
 
 #include "base/macros.h"
 #include "base/time/time.h"
 #include "media/base/data_source.h"
 #include "media/base/demuxer_stream.h"
 #include "media/base/demuxer_stream_provider.h"
 #include "media/base/eme_constants.h"
 #include "media/base/media_export.h"
 #include "media/base/pipeline_status.h"
 #include "media/base/ranges.h"
 
 namespace media {
 
 class TextTrackConfig;
+class MediaTracks;
 
 class MEDIA_EXPORT DemuxerHost {
  public:
   // Notify the host that buffered time ranges have changed. Note that buffered
   // time ranges can grow (when new media data is appended), but they can also
   // shrink (when buffering reaches limit capacity and some buffered data
   // becomes evicted, e.g. due to MSE GC algorithm, or by explicit removal of
   // ranges directed by MSE web app).
   virtual void OnBufferedTimeRangesChanged(
       const Ranges<base::TimeDelta>& ranges) = 0;
@@ skipping 19 matching lines @@
 
 class MEDIA_EXPORT Demuxer : public DemuxerStreamProvider {
  public:
   // A new potentially encrypted stream has been parsed.
   // First parameter - The type of initialization data.
   // Second parameter - The initialization data associated with the stream.
   typedef base::Callback<void(EmeInitDataType type,
                               const std::vector<uint8_t>& init_data)>
       EncryptedMediaInitDataCB;
 
+  // Notifies demuxer clients that media track configuration has been updated
+  // (e.g. the inital stream metadata has been parsed successfully, or a new

[wolenetz, 2016/03/05 01:47:43]

nit:initial

+  // init segment has been parsed successfully in MSE case).
+  typedef base::Callback<void(scoped_ptr<MediaTracks>)> MediaTracksUpdatedCB;
+
   Demuxer();
   ~Demuxer() override;
 
   // Returns the name of the demuxer for logging purpose.
   virtual std::string GetDisplayName() const = 0;
 
   // Completes initialization of the demuxer.
   //
   // The demuxer does not own |host| as it is guaranteed to outlive the
   // lifetime of the demuxer. Don't delete it!  |status_cb| must only be run
@@ skipping 24 matching lines @@
   // Returns the memory usage in bytes for the demuxer.
   virtual int64_t GetMemoryUsage() const = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(Demuxer);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_DEMUXER_H_