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

Source/core/loader/appcache/ApplicationCache.h

Index: Source/core/loader/appcache/ApplicationCache.h
diff --git a/Source/core/loader/appcache/ApplicationCache.h b/Source/core/loader/appcache/ApplicationCache.h
index 7d0ae3b64f7650d30f7492ca4bb450a29f4ed2de..3f2efec95d3bebd551562260b2295a332fde1be7 100644
--- a/Source/core/loader/appcache/ApplicationCache.h
+++ b/Source/core/loader/appcache/ApplicationCache.h
@@ -42,7 +42,8 @@ class LocalFrame;
 class KURL;
 
 class ApplicationCache FINAL : public RefCountedWillBeRefCountedGarbageCollected<ApplicationCache>, public ScriptWrappable, public EventTargetWithInlineData, public DOMWindowProperty {
-    DEFINE_EVENT_TARGET_REFCOUNTING(RefCountedWillBeRefCountedGarbageCollected<ApplicationCache>);
+    REFCOUNTED_EVENT_TARGET(ApplicationCache);
+    WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(ApplicationCache);
 public:
     static PassRefPtrWillBeRawPtr<ApplicationCache> create(LocalFrame* frame)
     {
@@ -73,8 +74,6 @@ public:
 
     static const AtomicString& toEventType(ApplicationCacheHost::EventID);
 
-    void trace(Visitor*) { }
-
 private:
     explicit ApplicationCache(LocalFrame*);