Revert of Oilpan: Move MediaStreamSource, MediaStreamComponent and MediaStreamDescriptor

Source/modules/mediastream/MediaStreamTrack.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  * Copyright (C) 2011 Ericsson AB. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 41 matching lines @@
     , m_isIteratingRegisteredMediaStreams(false)
     , m_stopped(false)
     , m_component(component)
 {
     ScriptWrappable::init(this);
     m_component->source()->addObserver(this);
 }
 
 MediaStreamTrack::~MediaStreamTrack()
 {
+    m_component->source()->removeObserver(this);
 }
 
 String MediaStreamTrack::kind() const
 {
     DEFINE_STATIC_LOCAL(String, audioKind, ("audio"));
     DEFINE_STATIC_LOCAL(String, videoKind, ("video"));
 
     switch (m_component->source()->type()) {
     case MediaStreamSource::TypeAudio:
         return audioKind;
@@ skipping 67 matching lines @@
         return;
 
     m_readyState = MediaStreamSource::ReadyStateEnded;
     MediaStreamCenter::instance().didStopMediaStreamTrack(component());
     dispatchEvent(Event::create(EventTypeNames::ended));
     propagateTrackEnded();
 }
 
 MediaStreamTrack* MediaStreamTrack::clone(ExecutionContext* context)
 {
-    MediaStreamComponent* clonedComponent = MediaStreamComponent::create(component()->source());
-    MediaStreamTrack* clonedTrack = MediaStreamTrack::create(context, clonedComponent);
-    MediaStreamCenter::instance().didCreateMediaStreamTrack(clonedComponent);
+    RefPtr<MediaStreamComponent> clonedComponent = MediaStreamComponent::create(component()->source());
+    MediaStreamTrack* clonedTrack = MediaStreamTrack::create(context, clonedComponent.get());
+    MediaStreamCenter::instance().didCreateMediaStreamTrack(clonedComponent.get());
     return clonedTrack;
 }
 
 bool MediaStreamTrack::ended() const
 {
     return m_stopped || (m_readyState == MediaStreamSource::ReadyStateEnded);
 }
 
 void MediaStreamTrack::sourceChangedState()
 {
@@ skipping 60 matching lines @@
 }
 
 ExecutionContext* MediaStreamTrack::executionContext() const
 {
     return ActiveDOMObject::executionContext();
 }
 
 void MediaStreamTrack::trace(Visitor* visitor)
 {
     visitor->trace(m_registeredMediaStreams);
-    visitor->trace(m_component);
     EventTargetWithInlineData::trace(visitor);
-    MediaStreamSource::Observer::trace(visitor);
 }
 
 } // namespace blink