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

Source/core/html/HTMLElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2011 Motorola Mobility. 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 593 matching lines @@
     if (equalIgnoringCase(value, "yes") || equalIgnoringCase(value, ""))
         return TranslateAttributeYes;
     if (equalIgnoringCase(value, "no"))
         return TranslateAttributeNo;
 
     return TranslateAttributeInherit;
 }
 
 bool HTMLElement::translate() const
 {
-    for (const Node* n = this; n; n = n->parentNode()) {
-        if (n->isHTMLElement()) {
-            TranslateAttributeMode mode = toHTMLElement(n)->translateAttributeMode();
-            if (mode != TranslateAttributeInherit) {
-                ASSERT(mode == TranslateAttributeYes || mode == TranslateAttributeNo);
-                return mode == TranslateAttributeYes;
-            }
+    for (const HTMLElement* element = this; element; element = Traversal<HTMLElement>::firstAncestor(*element)) {
+        TranslateAttributeMode mode = element->translateAttributeMode();
+        if (mode != TranslateAttributeInherit) {
+            ASSERT(mode == TranslateAttributeYes || mode == TranslateAttributeNo);
+            return mode == TranslateAttributeYes;
         }
     }
 
     // Default on the root element is translate=yes.
     return true;
 }
 
 void HTMLElement::setTranslate(bool enable)
 {
     setAttribute(translateAttr, enable ? "yes" : "no");
 }
 
 HTMLFormElement* HTMLElement::findFormAncestor() const
 {
-    for (ContainerNode* ancestor = parentNode(); ancestor; ancestor = ancestor->parentNode()) {
-        if (isHTMLFormElement(*ancestor))
-            return toHTMLFormElement(ancestor);
-    }
-    return 0;
+    return Traversal<HTMLFormElement>::firstAncestor(*this);
 }
 
 static inline bool elementAffectsDirectionality(const Node* node)
 {
     return node->isHTMLElement() && (isHTMLBDIElement(*node) || toHTMLElement(node)->hasAttribute(dirAttr));
 }
 
 static void setHasDirAutoFlagRecursively(Node* firstNode, bool flag, Node* lastNode = 0)
 {
     firstNode->setSelfOrAncestorHasDirAutoAttribute(flag);
@@ skipping 318 matching lines @@
 #ifndef NDEBUG
 
 // For use in the debugger
 void dumpInnerHTML(WebCore::HTMLElement*);
 
 void dumpInnerHTML(WebCore::HTMLElement* element)
 {
     printf("%s\n", element->innerHTML().ascii().data());
 }
 #endif