Revert of [Oilpan] Move MediaStream{Source|Component|Descriptor} to Oilpan heap

third_party/WebKit/Source/modules/mediastream/MediaStreamTrack.cpp

Index: third_party/WebKit/Source/modules/mediastream/MediaStreamTrack.cpp
diff --git a/third_party/WebKit/Source/modules/mediastream/MediaStreamTrack.cpp b/third_party/WebKit/Source/modules/mediastream/MediaStreamTrack.cpp
index 9c8f7c946766e9d46e2600508d2644020323fc63..4b1fe41c63082edce7c7057775782fa25dc4f201 100644
--- a/third_party/WebKit/Source/modules/mediastream/MediaStreamTrack.cpp
+++ b/third_party/WebKit/Source/modules/mediastream/MediaStreamTrack.cpp
@@ -60,6 +60,7 @@
 
 MediaStreamTrack::~MediaStreamTrack()
 {
+    m_component->source()->removeObserver(this);
 }
 
 String MediaStreamTrack::kind() const
@@ -162,9 +163,9 @@
 
 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;
 }
 
@@ -204,6 +205,11 @@
     m_isIteratingRegisteredMediaStreams = false;
 }
 
+MediaStreamComponent* MediaStreamTrack::component()
+{
+    return m_component.get();
+}
+
 void MediaStreamTrack::stop()
 {
     m_stopped = true;
@@ -242,7 +248,6 @@
 DEFINE_TRACE(MediaStreamTrack)
 {
     visitor->trace(m_registeredMediaStreams);
-    visitor->trace(m_component);
     RefCountedGarbageCollectedEventTargetWithInlineData<MediaStreamTrack>::trace(visitor);
     ActiveDOMObject::trace(visitor);
 }