Oilpan: Allocate all EventTarget derived types on the manged heap.

Source/modules/mediastream/RTCDataChannel.h

Index: Source/modules/mediastream/RTCDataChannel.h
diff --git a/Source/modules/mediastream/RTCDataChannel.h b/Source/modules/mediastream/RTCDataChannel.h
index d6bcb9414c9a77944d29eb40800344c3ecd5eb55..66e2a87e17858ae61e1a71dc44efebab8c8ed96c 100644
--- a/Source/modules/mediastream/RTCDataChannel.h
+++ b/Source/modules/mediastream/RTCDataChannel.h
@@ -44,8 +44,9 @@ namespace WebCore {
 class Blob;
 class ExceptionState;
 
-class RTCDataChannel FINAL : public RefCounted<RTCDataChannel>, public ScriptWrappable, public EventTargetWithInlineData, public blink::WebRTCDataChannelHandlerClient {
+class RTCDataChannel FINAL : public RefCountedWillBeRefCountedGarbageCollected<RTCDataChannel>, public ScriptWrappable, public EventTargetWithInlineData, public blink::WebRTCDataChannelHandlerClient {
     REFCOUNTED_EVENT_TARGET(RTCDataChannel);
+    WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(RTCDataChannel);
 public:
     static PassRefPtr<RTCDataChannel> create(ExecutionContext*, PassOwnPtr<blink::WebRTCDataChannelHandler>);
     static PassRefPtr<RTCDataChannel> create(ExecutionContext*, blink::WebRTCPeerConnectionHandler*, const String& label, const blink::WebRTCDataChannelInit&, ExceptionState&);
@@ -86,6 +87,8 @@ public:
     virtual const AtomicString& interfaceName() const OVERRIDE;
     virtual ExecutionContext* executionContext() const OVERRIDE;
 
+    virtual void trace(Visitor*) OVERRIDE;
+
 private:
     RTCDataChannel(ExecutionContext*, PassOwnPtr<blink::WebRTCDataChannelHandler>);
 
@@ -113,7 +116,7 @@ private:
     BinaryType m_binaryType;
 
     Timer<RTCDataChannel> m_scheduledEventTimer;
-    WillBePersistentHeapVector<RefPtrWillBeMember<Event> > m_scheduledEvents;
+    WillBeHeapVector<RefPtrWillBeMember<Event> > m_scheduledEvents;
 };
 
 } // namespace WebCore