Use nullptr_t for RefPtr, PassRefPtr and RawPtr.

Source/core/events/FocusEvent.cpp

 /*
  * 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 15 matching lines @@
 #include "config.h"
 #include "core/events/FocusEvent.h"
 
 #include "core/events/Event.h"
 #include "core/events/EventDispatcher.h"
 #include "core/events/ThreadLocalEventNames.h"
 
 namespace WebCore {
 
 FocusEventInit::FocusEventInit()
-    : relatedTarget(0)
+    : relatedTarget(nullptr)
 {
 }
 
 const AtomicString& FocusEvent::interfaceName() const
 {
     return EventNames::FocusEvent;
 }
 
 bool FocusEvent::isFocusEvent() const
 {
@@ skipping 77 matching lines @@
 {
 }
 
 bool FocusOutEventDispatchMediator::dispatchEvent(EventDispatcher* dispatcher) const
 {
     event()->eventPath().adjustForRelatedTarget(dispatcher->node(), event()->relatedTarget());
     return EventDispatchMediator::dispatchEvent(dispatcher);
 }
 
 } // namespace WebCore