Remove ExecutionContext::lifecycleNotifier.

Source/core/dom/ExecutionContext.cpp

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  * Copyright (C) 2012 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 183 matching lines @@
 const KURL& ExecutionContext::url() const
 {
     return virtualURL();
 }
 
 KURL ExecutionContext::completeURL(const String& url) const
 {
     return virtualCompleteURL(url);
 }
 
-bool ExecutionContext::isIteratingOverObservers() const
-{
-    return m_lifecycleNotifier && m_lifecycleNotifier->isIteratingOverObservers();
-}
-
 void ExecutionContext::allowWindowInteraction()
 {
     ++m_windowInteractionTokens;
 }
 
 void ExecutionContext::consumeWindowInteraction()
 {
     if (m_windowInteractionTokens == 0)
         return;
     --m_windowInteractionTokens;
@@ skipping 11 matching lines @@
 {
 #if ENABLE(OILPAN)
     visitor->trace(m_pendingExceptions);
     visitor->trace(m_publicURLManager);
     HeapSupplementable<ExecutionContext>::trace(visitor);
 #endif
     ContextLifecycleNotifier::trace(visitor);
 }
 
 } // namespace blink