Remove SourceBuffer media tracks on detach from media element

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

 /*
  * 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 197 matching lines @@
 
     ASSERT(isClosed());
 
     m_activeSourceBuffers->clear();
 
     // Clear SourceBuffer references to this object.
     for (unsigned long i = 0; i < m_sourceBuffers->length(); ++i)
         m_sourceBuffers->item(i)->removedFromMediaSource();
     m_sourceBuffers->clear();
 
+    m_attachedElement.clear();
+
     scheduleEvent(EventTypeNames::sourceclose);
 }
 
 bool MediaSource::isUpdating() const
 {
     // Return true if any member of |m_sourceBuffers| is updating.
     for (unsigned long i = 0; i < m_sourceBuffers->length(); ++i) {
         if (m_sourceBuffers->item(i)->updating())
             return true;
     }
@@ skipping 215 matching lines @@
 
 void MediaSource::setReadyState(const AtomicString& state)
 {
     ASSERT(state == openKeyword() || state == closedKeyword() || state == endedKeyword());
 
     AtomicString oldState = readyState();
     WTF_LOG(Media, "MediaSource::setReadyState() %p : %s -> %s", this, oldState.ascii().data(), state.ascii().data());
 
     if (state == closedKeyword()) {
         m_webMediaSource.clear();
-        m_attachedElement.clear();
     }
 
     if (oldState == state)
         return;
 
     m_readyState = state;
 
     onReadyStateChange(oldState, state);
 }
 
@@ skipping 150 matching lines @@
 
     m_asyncEventQueue->enqueueEvent(event);
 }
 
 URLRegistry& MediaSource::registry() const
 {
     return MediaSourceRegistry::registry();
 }
 
 } // namespace blink