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

Source/core/html/HTMLTextAreaElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2010 Apple Inc. All rights reserved.
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2007 Samuel Weinig (sam@webkit.org)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 82 matching lines @@
     , m_wrap(SoftWrap)
     , m_placeholder(0)
     , m_isDirty(false)
     , m_wasModifiedByUser(false)
 {
     ASSERT(hasTagName(textareaTag));
     setFormControlValueMatchesRenderer(true);
     ScriptWrappable::init(this);
 }
 
-PassRefPtr<HTMLTextAreaElement> HTMLTextAreaElement::create(const QualifiedName& tagName, Document* document, HTMLFormElement* form)
+Result<HTMLTextAreaElement> HTMLTextAreaElement::create(const QualifiedName& tagName, Document* document, HTMLFormElement* form)
 {
-    RefPtr<HTMLTextAreaElement> textArea = adoptRef(new HTMLTextAreaElement(tagName, document, form));
+    Handle<HTMLTextAreaElement> textArea = adoptNode(new HTMLTextAreaElement(tagName, document, form));
     textArea->ensureUserAgentShadowRoot();
-    return textArea.release();
+    return textArea;
 }
 
 void HTMLTextAreaElement::didAddUserAgentShadowRoot(ShadowRoot* root)
 {
     root->appendChild(TextControlInnerTextElement::create(document()), ASSERT_NO_EXCEPTION);
 }
 
 const AtomicString& HTMLTextAreaElement::formControlType() const
 {
     DEFINE_STATIC_LOCAL(const AtomicString, textarea, ("textarea", AtomicString::ConstructFromLiteral));
@@ skipping 436 matching lines @@
     if (!m_placeholder) {
         RefPtr<HTMLDivElement> placeholder = HTMLDivElement::create(document());
         m_placeholder = placeholder.get();
         m_placeholder->setPseudo(AtomicString("-webkit-input-placeholder", AtomicString::ConstructFromLiteral));
         userAgentShadowRoot()->insertBefore(m_placeholder, innerTextElement()->nextSibling(), ASSERT_NO_EXCEPTION);
     }
     m_placeholder->setInnerText(placeholderText, ASSERT_NO_EXCEPTION);
     fixPlaceholderRenderer(m_placeholder, innerTextElement());
 }
 
+void HTMLTextAreaElement::acceptHeapVisitor(Visitor* visitor) const
+{
+    HTMLTextFormControlElement::acceptHeapVisitor(visitor);
 }
+
+}