Add UseCounters for name attribute matching of <map> and <input type=radio>

third_party/WebKit/Source/core/dom/TreeScope.cpp

 /*
  * Copyright (C) 2011 Google Inc. All Rights Reserved.
  * Copyright (C) 2012 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
@@ skipping 178 matching lines @@
 }
 
 HTMLMapElement* TreeScope::getImageMap(const String& url) const
 {
     if (url.isNull())
         return nullptr;
     if (!m_imageMapsByName)
         return nullptr;
     size_t hashPos = url.find('#');
     String name = hashPos == kNotFound ? url : url.substring(hashPos + 1);
-    if (rootNode().document().isHTMLDocument())
-        return toHTMLMapElement(m_imageMapsByName->getElementByLowercasedMapName(AtomicString(name.lower()), this));
-    return toHTMLMapElement(m_imageMapsByName->getElementByMapName(AtomicString(name), this));
+    HTMLMapElement* map = toHTMLMapElement(rootNode().document().isHTMLDocument()
+        ? m_imageMapsByName->getElementByLowercasedMapName(AtomicString(name.lower()), this)
+        : m_imageMapsByName->getElementByMapName(AtomicString(name), this));
+    if (!map || !rootNode().document().isHTMLDocument())
+        return map;
+    const AtomicString& nameValue = map->fastGetAttribute(nameAttr);
+    if (nameValue.isNull())
+        return map;
+    String strippedName = nameValue;
+    if (strippedName.startsWith('#'))
+        strippedName = strippedName.substring(1);
+    if (strippedName == name)
+        UseCounter::count(rootNode().document(), UseCounter::MapNameMatchingStrict);
+    else if (equalIgnoringASCIICase(strippedName, name))
+        UseCounter::count(rootNode().document(), UseCounter::MapNameMatchingASCIICaseless);
+    else
+        UseCounter::count(rootNode().document(), UseCounter::MapNameMatchingUnicodeLower);
+    return map;
 }
 
 static bool pointWithScrollAndZoomIfPossible(const Document& document, IntPoint& point)
 {
     LocalFrame* frame = document.frame();
     if (!frame)
         return false;
     FrameView* frameView = frame->view();
     if (!frameView)
         return false;
@@ skipping 308 matching lines @@
     visitor->trace(m_parentTreeScope);
     visitor->trace(m_idTargetObserverRegistry);
     visitor->trace(m_selection);
     visitor->trace(m_elementsById);
     visitor->trace(m_imageMapsByName);
     visitor->trace(m_scopedStyleResolver);
     visitor->trace(m_radioButtonGroupScope);
 }
 
 } // namespace blink