Use nullptr_t for RefPtr, PassRefPtr and RawPtr.

Source/core/rendering/RenderMenuList.cpp

 /*
  * This file is part of the select element renderer in WebCore.
  *
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  *               2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 52 matching lines @@
 {
     ASSERT(element);
     ASSERT(element->isHTMLElement());
     ASSERT(element->hasTagName(HTMLNames::selectTag));
 }
 
 RenderMenuList::~RenderMenuList()
 {
     if (m_popup)
         m_popup->disconnectClient();
-    m_popup = 0;
+    m_popup = nullptr;
 }
 
 // FIXME: Instead of this hack we should add a ShadowRoot to <select> with no insertion point
 // to prevent children from rendering.
 bool RenderMenuList::isChildAllowed(RenderObject* object, RenderStyle*) const
 {
     return object->isAnonymous() && !object->isRenderFullScreen();
 }
 
 void RenderMenuList::createInnerBlock()
@@ skipping 478 matching lines @@
     HTMLElement* element = listItems[listIndex];
     return element->hasTagName(optionTag) && toHTMLOptionElement(element)->selected();
 }
 
 void RenderMenuList::setTextFromItem(unsigned listIndex)
 {
     setTextFromOption(selectElement()->listToOptionIndex(listIndex));
 }
 
 }