[oilpan] Completely move HTMLFormControlElement's hierarchy to the managed heap

Source/core/html/HTMLOutputElement.cpp

 /*
  * Copyright (c) 2010 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 29 matching lines @@
 inline HTMLOutputElement::HTMLOutputElement(const QualifiedName& tagName, Document* document, HTMLFormElement* form)
     : HTMLFormControlElement(tagName, document, form)
     , m_isDefaultValueMode(true)
     , m_isSetTextContentInProgress(false)
     , m_defaultValue("")
     , m_tokens(DOMSettableTokenList::create())
 {
     ScriptWrappable::init(this);
 }
 
-PassRefPtr<HTMLOutputElement> HTMLOutputElement::create(const QualifiedName& tagName, Document* document, HTMLFormElement* form)
+Result<HTMLOutputElement> HTMLOutputElement::create(const QualifiedName& tagName, Document* document, HTMLFormElement* form)
 {
-    return adoptRef(new HTMLOutputElement(tagName, document, form));
+    return adoptNode(new HTMLOutputElement(tagName, document, form));
 }
 
 const AtomicString& HTMLOutputElement::formControlType() const
 {
     DEFINE_STATIC_LOCAL(const AtomicString, output, ("output", AtomicString::ConstructFromLiteral));
     return output;
 }
 
 bool HTMLOutputElement::supportsFocus() const
 {
@@ skipping 72 matching lines @@
         setTextContentInternal(value);
 }
 
 void HTMLOutputElement::setTextContentInternal(const String& value)
 {
     ASSERT(!m_isSetTextContentInProgress);
     m_isSetTextContentInProgress = true;
     setTextContent(value, IGNORE_EXCEPTION);
 }
 
+void HTMLOutputElement::acceptHeapVisitor(Visitor* visitor) const
+{
+    HTMLFormControlElement::acceptHeapVisitor(visitor);
+}
+
 } // namespace