Oilpan: move custom element objects to the heap.

Source/core/dom/custom/CustomElementObserver.h

 /*
  * 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:
  *
  * 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 13 matching lines @@
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef CustomElementObserver_h
 #define CustomElementObserver_h
 
+#include "platform/heap/Handle.h"
 #include "wtf/HashMap.h"
 
 namespace WebCore {
 
 class Element;
 
-class CustomElementObserver {
+class CustomElementObserver : public NoBaseWillBeGarbageCollectedFinalized<CustomElementObserver> {
 public:
-    CustomElementObserver() { }
     virtual ~CustomElementObserver() { }
 
     // API for CustomElement to kick off notifications
 
     static void notifyElementDidFinishParsingChildren(Element*);
     static void notifyElementWasDestroyed(Element*);
 
+    virtual void trace(Visitor*) { }
+
 protected:
+    CustomElementObserver() { }
+
     void observe(Element*);
     void unobserve(Element*);
 
     virtual void elementDidFinishParsingChildren(Element*) = 0;
     virtual void elementWasDestroyed(Element* element) { unobserve(element); }
-
-private:
-    // Maps elements to the observer watching them. At most one per
-    // element at a time.
-    typedef HashMap<Element*, CustomElementObserver*> ElementObserverMap;
-    static ElementObserverMap& elementObservers();
 };
 
 }
 
 #endif // CustomElementObserver_h