Have MutationObserverRegistration deal with references instead of pointers

Source/core/dom/MutationObserver.cpp

 /*
  * Copyright (C) 2011 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 119 matching lines @@
     if (!((options & CharacterData) || !(options & CharacterDataOldValue))) {
         exceptionState.throwTypeError("The options object may only set 'characterDataOldValue' to true when 'characterData' is true or not present.");
         return;
     }
 
     if (!(options & (Attributes | CharacterData | ChildList))) {
         exceptionState.throwTypeError("The options object must set at least one of 'attributes', 'characterData', or 'childList' to true.");
         return;
     }
 
-    node->registerMutationObserver(this, options, attributeFilter);
+    node->registerMutationObserver(*this, options, attributeFilter);
 }
 
 Vector<RefPtr<MutationRecord> > MutationObserver::takeRecords()
 {
     Vector<RefPtr<MutationRecord> > records;
     records.swap(m_records);
     InspectorInstrumentation::didClearAllMutationRecords(m_callback->executionContext(), this);
     return records;
 }
 
@@ skipping 117 matching lines @@
     std::sort(observers.begin(), observers.end(), ObserverLessThan());
     for (size_t i = 0; i < observers.size(); ++i) {
         if (observers[i]->canDeliver())
             observers[i]->deliver();
         else
             suspendedMutationObservers().add(observers[i]);
     }
 }
 
 } // namespace WebCore