Implement Custom Elements' entered and left document callbacks.

Source/core/dom/CustomElementCallbackQueue.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 14 matching lines @@
  * 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 CustomElementCallbackQueue_h
 #define CustomElementCallbackQueue_h
 
 #include "core/dom/CustomElementCallbackInvocation.h"
-#include "core/dom/CustomElementLifecycleCallbacks.h"
 #include "wtf/PassOwnPtr.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefPtr.h"
 #include "wtf/Vector.h"
 
 namespace WebCore {
 
 class CustomElementCallbackQueue {
     WTF_MAKE_NONCOPYABLE(CustomElementCallbackQueue);
 public:
-    static PassOwnPtr<CustomElementCallbackQueue> create(PassRefPtr<CustomElementLifecycleCallbacks>, PassRefPtr<Element>);
+    static PassOwnPtr<CustomElementCallbackQueue> create(PassRefPtr<Element>);
 
     typedef int ElementQueue;
     ElementQueue owner() { return m_owner; }
     void setOwner(ElementQueue newOwner)
     {
         // ElementCallbackQueues only migrate towards the top of the
         // processing stack.
         ASSERT(newOwner >= m_owner);
         m_owner = newOwner;
     }
 
     void append(PassOwnPtr<CustomElementCallbackInvocation> invocation) { m_queue.append(invocation); }
-
     void processInElementQueue(ElementQueue);
 
 private:
-    CustomElementCallbackQueue(PassRefPtr<CustomElementLifecycleCallbacks>, PassRefPtr<Element>);
+    CustomElementCallbackQueue(PassRefPtr<Element>);
 
-    RefPtr<CustomElementLifecycleCallbacks> m_callbacks;
     RefPtr<Element> m_element;
     Vector<OwnPtr<CustomElementCallbackInvocation> > m_queue;
     ElementQueue m_owner;
     size_t m_index;
 };
 
 }
 
 #endif // CustomElementCallbackQueue_h