Have HTMLFormElement's named getter return a RadioNodeList.

Source/core/dom/Node.cpp

Index: Source/core/dom/Node.cpp
diff --git a/Source/core/dom/Node.cpp b/Source/core/dom/Node.cpp
index abea9efac4e4575ab753b4659de30b15875035a5..1bc66db50a4ac8bb1c31658fcc1475cdcf6b38dd 100644
--- a/Source/core/dom/Node.cpp
+++ b/Source/core/dom/Node.cpp
@@ -1352,9 +1352,12 @@ PassRefPtr<NodeList> Node::getElementsByClassName(const String& classNames)
     return ensureRareData().ensureNodeLists().addCacheWithName<ClassNodeList>(this, ClassNodeListType, classNames);
 }
 
-PassRefPtr<RadioNodeList> Node::radioNodeList(const AtomicString& name)
+PassRefPtr<RadioNodeList> Node::radioNodeList(const AtomicString& name, bool onlyMatchImgElements)
 {
     ASSERT(hasTagName(formTag) || hasTagName(fieldsetTag));
+    if (onlyMatchImgElements)
+        return static_pointer_cast<RadioNodeList>(ensureRareData().ensureNodeLists().addCacheWithAtomicName<RadioImgNodeList>(this, RadioNodeListType, name));
+
     return ensureRareData().ensureNodeLists().addCacheWithAtomicName<RadioNodeList>(this, RadioNodeListType, name);
 }