Implement type=radio and radiogroup attribute for menuitem.

Source/core/html/HTMLMenuItemElement.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/html/HTMLMenuItemElement.h"
 
 #include "core/HTMLNames.h"
+#include "core/dom/ElementTraversal.h"
 #include "core/events/Event.h"
 
 namespace blink {
 
 using namespace HTMLNames;
 
 inline HTMLMenuItemElement::HTMLMenuItemElement(Document& document)
     : HTMLElement(HTMLNames::menuitemTag, document)
 {
 }
 
 void HTMLMenuItemElement::defaultEventHandler(Event* event)
 {
     if (event->type() == EventTypeNames::click) {
         if (equalIgnoringCase(fastGetAttribute(typeAttr), "checkbox")) {
             if (fastHasAttribute(checkedAttr))
                 removeAttribute(checkedAttr);
             else
                 setAttribute(checkedAttr, "checked");
+        } else if (equalIgnoringCase(fastGetAttribute(typeAttr), "radio")) {
+            if (Element* parent = parentElement()) {
+                Element* nextElement = ElementTraversal::firstWithin(*parent);
+                String group = fastGetAttribute(radiogroupAttr);
+                while (nextElement) {

[tkent, 2014/12/09 13:02:26]

for (HTMLMenuItemElement& menuItem :
Traversal<HTMLMenuItemElement>::childrenOf(*parent)) {
    ....
}

+                    if (isHTMLMenuItemElement(*nextElement) && nextElement->fastHasAttribute(checkedAttr) && equalIgnoringCase(nextElement->fastGetAttribute(radiogroupAttr), group)) {

[tkent, 2014/12/09 12:43:43]

Why equalsIgnoringCase?  The specification says "exactly matches"

+                        nextElement->removeAttribute(checkedAttr);
+                    }
+                    nextElement = Traversal<HTMLElement>::nextSibling(*nextElement);
+                }
+            }
+            setAttribute(checkedAttr, "checked");
         }
         event->setDefaultHandled();
     }
 }
 
 DEFINE_NODE_FACTORY(HTMLMenuItemElement)
 
 } // namespace blink