Oilpan: Replace RefPtrs to Node and its subclasses in core/html with Oilpan transitin types.

Source/core/html/track/vtt/VTTElement.cpp

 /*
  * Copyright (C) 2013 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 65 matching lines @@
     return adoptRefWillBeRefCountedGarbageCollected(new VTTElement(nodeType, document));
 }
 
 PassRefPtrWillBeRawPtr<Element> VTTElement::cloneElementWithoutAttributesAndChildren()
 {
     RefPtrWillBeRawPtr<VTTElement> clone = create(static_cast<VTTNodeType>(m_webVTTNodeType), &document());
     clone->setLanguage(m_language);
     return clone.release();
 }
 
-PassRefPtr<HTMLElement> VTTElement::createEquivalentHTMLElement(Document& document)
+PassRefPtrWillBeRawPtr<HTMLElement> VTTElement::createEquivalentHTMLElement(Document& document)
 {
-    RefPtr<HTMLElement> htmlElement;
+    RefPtrWillBeRawPtr<HTMLElement> htmlElement = nullptr;
     switch (m_webVTTNodeType) {
     case VTTNodeTypeClass:
     case VTTNodeTypeLanguage:
     case VTTNodeTypeVoice:
         htmlElement = HTMLElementFactory::createHTMLElement(HTMLNames::spanTag.localName(), document);
         htmlElement.get()->setAttribute(HTMLNames::titleAttr, getAttribute(voiceAttributeName()));
         htmlElement.get()->setAttribute(HTMLNames::langAttr, getAttribute(langAttributeName()));
         break;
     case VTTNodeTypeItalic:
         htmlElement = HTMLElementFactory::createHTMLElement(HTMLNames::iTag.localName(), document);
@@ skipping 13 matching lines @@
     default:
         ASSERT_NOT_REACHED();
     }
 
     htmlElement.get()->setAttribute(HTMLNames::classAttr, getAttribute(HTMLNames::classAttr));
     return htmlElement;
 }
 
 } // namespace WebCore