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

Source/core/editing/FrameSelection.cpp

Index: Source/core/editing/FrameSelection.cpp
diff --git a/Source/core/editing/FrameSelection.cpp b/Source/core/editing/FrameSelection.cpp
index 0c6083da2dbe8c3e0c54be10ef36358e84826cc6..ccf5d819810d8996ec86a9d5ca8a3fb0ab2bee86 100644
--- a/Source/core/editing/FrameSelection.cpp
+++ b/Source/core/editing/FrameSelection.cpp
@@ -1751,15 +1751,12 @@ HTMLFormElement* FrameSelection::currentForm() const
         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.