Deliver change notifications to SourceBuffer track lists.

third_party/WebKit/Source/modules/mediasource/MediaSource.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 75 matching lines @@
     static bool isTypeSupported(const String& type);
 
     // HTMLMediaSource
     bool attachToElement(HTMLMediaElement*) override;
     void setWebMediaSourceAndOpen(std::unique_ptr<WebMediaSource>) override;
     void close() override;
     bool isClosed() const override;
     double duration() const override;
     TimeRanges* buffered() const override;
     TimeRanges* seekable() const override;
+    void onTrackChanged(TrackBase*) override;
 
     // EventTarget interface
     const AtomicString& interfaceName() const override;
     ExecutionContext* getExecutionContext() const override;
 
     // ActiveScriptWrappable
     bool hasPendingActivity() const final;
 
     // ActiveDOMObject interface
     void stop() override;
@@ skipping 38 matching lines @@
     Member<SourceBufferList> m_activeSourceBuffers;
 
     Member<TimeRanges> m_liveSeekableRange;
 
     int m_addedToRegistryCounter;
 };
 
 } // namespace blink
 
 #endif // MediaSource_h