IDL: Use Nullable for union type return value

Source/core/html/HTMLFormElement.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, 2009 Apple Inc. All rights reserved.
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.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 799 matching lines @@
     document().formController().restoreControlStateIn(*this);
     m_didFinishParsingChildren = true;
 }
 
 void HTMLFormElement::copyNonAttributePropertiesFromElement(const Element& source)
 {
     m_wasDemoted = static_cast<const HTMLFormElement&>(source).m_wasDemoted;
     HTMLElement::copyNonAttributePropertiesFromElement(source);
 }
 
-void HTMLFormElement::anonymousNamedGetter(const AtomicString& name, bool& returnValue0Enabled, RefPtrWillBeRawPtr<RadioNodeList>& returnValue0, bool& returnValue1Enabled, RefPtrWillBeRawPtr<Element>& returnValue1)
+void HTMLFormElement::anonymousNamedGetter(const AtomicString& name, RefPtrWillBeRawPtr<RadioNodeList>& returnValue0, RefPtrWillBeRawPtr<Element>& returnValue1)
 {
     // Call getNamedElements twice, first time check if it has a value
     // and let HTMLFormElement update its cache.
     // See issue: 867404
     {
         WillBeHeapVector<RefPtrWillBeMember<Element> > elements;
         getNamedElements(name, elements);
         if (elements.isEmpty())
             return;
     }
 
     // Second call may return different results from the first call,
     // but if the first the size cannot be zero.
     WillBeHeapVector<RefPtrWillBeMember<Element> > elements;
     getNamedElements(name, elements);
     ASSERT(!elements.isEmpty());
 
     if (elements.size() == 1) {
-        returnValue1Enabled = true;
         returnValue1 = elements.at(0);
         return;
     }
 
     bool onlyMatchImg = !elements.isEmpty() && isHTMLImageElement(*elements.first());
-    returnValue0Enabled = true;
     returnValue0 = radioNodeList(name, onlyMatchImg);
 }
 
 void HTMLFormElement::setDemoted(bool demoted)
 {
     if (demoted)
         UseCounter::count(document(), UseCounter::DemotedFormElement);
     m_wasDemoted = demoted;
 }
 
 } // namespace