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

Source/core/editing/FrameSelection.cpp

 /*
  * Copyright (C) 2004, 2008, 2009, 2010 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 1733 matching lines @@
 
 // We look for either the form containing the current focus, or for one immediately after it
 HTMLFormElement* FrameSelection::currentForm() const
 {
     // Start looking either at the active (first responder) node, or where the selection is.
     Node* start = m_frame->document()->focusedElement();
     if (!start)
         start = this->start().deprecatedNode();
 
     // Try walking up the node tree to find a form element.
-    Node* node;
-    for (node = start; node; node = node->parentNode()) {
-        if (isHTMLFormElement(*node))
-            return toHTMLFormElement(node);
-        if (node->isHTMLElement()) {
-            HTMLFormElement* owner = toHTMLElement(node)->formOwner();
-            if (owner)
-                return owner;
-        }
+    HTMLElement* element = !start || start->isHTMLElement() ? toHTMLElement(start) : Traversal<HTMLElement>::firstAncestor(*start);

[esprehn, 2014/03/21 07:58:33]

This seems like it makes the code less readable.

[Inactive, 2014/03/21 14:37:24]

Fair enough, I gave it another shot.

+    for (; element; element = Traversal<HTMLElement>::firstAncestor(*element)) {
+        if (isHTMLFormElement(*element))
+            return toHTMLFormElement(element);
+        if (HTMLFormElement* owner = element->formOwner())
+            return owner;
     }
 
     // Try walking forward in the node tree to find a form element.
     return scanForForm(start);
 }
 
 void FrameSelection::revealSelection(const ScrollAlignment& alignment, RevealExtentOption revealExtentOption)
 {
     LayoutRect rect;
 
@@ skipping 102 matching lines @@
     sel.showTreeForThis();
 }
 
 void showTree(const WebCore::FrameSelection* sel)
 {
     if (sel)
         sel->showTreeForThis();
 }
 
 #endif