Use nullptr_t for RefPtr, PassRefPtr and RawPtr.

Source/core/page/ContextMenuController.cpp

 /*
  * Copyright (C) 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Igalia S.L
  *
  * 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 42 matching lines @@
 PassOwnPtr<ContextMenuController> ContextMenuController::create(Page* page, ContextMenuClient* client)
 {
     return adoptPtr(new ContextMenuController(page, client));
 }
 
 void ContextMenuController::clearContextMenu()
 {
     m_contextMenu.clear();
     if (m_menuProvider)
         m_menuProvider->contextMenuCleared();
-    m_menuProvider = 0;
+    m_menuProvider = nullptr;
     m_hitTestResult = HitTestResult();
     m_client->clearContextMenu();
 }
 
 void ContextMenuController::documentDetached(Document* document)
 {
     if (Node* innerNode = m_hitTestResult.innerNode()) {
         // Invalidate the context menu info if its target document is detached.
         if (innerNode->document() == document)
             clearContextMenu();
@@ skipping 55 matching lines @@
     ASSERT(item->type() == ActionType || item->type() == CheckableActionType);
 
     if (item->action() < ContextMenuItemBaseCustomTag || item->action() > ContextMenuItemLastCustomTag)
         return;
 
     ASSERT(m_menuProvider);
     m_menuProvider->contextMenuItemSelected(item);
 }
 
 } // namespace WebCore