InitEvent should not do anything if dispatch flag is set.

third_party/WebKit/Source/modules/storage/StorageEvent.cpp

 /*
  * Copyright (C) 2008, 2009 Apple 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 63 matching lines @@
     if (initializer.hasNewValue())
         m_newValue = initializer.newValue();
     if (initializer.hasURL())
         m_url = initializer.url();
     if (initializer.hasStorageArea())
         m_storageArea = initializer.storageArea();
 }
 
 void StorageEvent::initStorageEvent(const AtomicString& type, bool canBubble, bool cancelable, const String& key, const String& oldValue, const String& newValue, const String& url, Storage* storageArea)
 {
-    if (dispatched())
+    if (isBeingDispatched())
         return;
 
     initEvent(type, canBubble, cancelable);
 
     m_key = key;
     m_oldValue = oldValue;
     m_newValue = newValue;
     m_url = url;
     m_storageArea = storageArea;
 }
 
 const AtomicString& StorageEvent::interfaceName() const
 {
     return EventNames::StorageEvent;
 }
 
 DEFINE_TRACE(StorageEvent)
 {
     visitor->trace(m_storageArea);
     Event::trace(visitor);
 }
 
 } // namespace blink