Add Traversal<*Element>::firstAncestor() API

Source/core/html/HTMLFrameElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Simon Hausmann (hausmann@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2006, 2009 Apple Inc. All rights reserved.
  *
  * 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 38 matching lines @@
 {
     // For compatibility, frames render even when display: none is set.
     return isURLAllowed();
 }
 
 RenderObject* HTMLFrameElement::createRenderer(RenderStyle*)
 {
     return new RenderFrame(this);
 }
 
-static inline HTMLFrameSetElement* containingFrameSetElement(Node* node)
-{
-    while ((node = node->parentNode())) {
-        if (isHTMLFrameSetElement(*node))
-            return toHTMLFrameSetElement(node);
-    }
-    return 0;
-}
-
 bool HTMLFrameElement::noResize() const
 {
     return hasAttribute(noresizeAttr);
 }
 
 void HTMLFrameElement::attach(const AttachContext& context)
 {
     HTMLFrameElementBase::attach(context);
 
-    if (HTMLFrameSetElement* frameSetElement = containingFrameSetElement(this)) {
+    if (HTMLFrameSetElement* frameSetElement = Traversal<HTMLFrameSetElement>::firstAncestor(*this)) {
         if (!m_frameBorderSet)
             m_frameBorder = frameSetElement->hasFrameBorder();
     }
 }
 
 void HTMLFrameElement::parseAttribute(const QualifiedName& name, const AtomicString& value)
 {
     if (name == frameborderAttr) {
         m_frameBorder = value.toInt();
         m_frameBorderSet = !value.isNull();
         // FIXME: If we are already attached, this has no effect.
     } else if (name == noresizeAttr) {
         if (renderer())
             renderer()->updateFromElement();
     } else
         HTMLFrameElementBase::parseAttribute(name, value);
 }
 
 } // namespace WebCore