Add use counters for elements used in Shadow DOM

third_party/WebKit/Source/core/html/HTMLContentElement.cpp

 /*
  * Copyright (C) 2011 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Neither the name of Google Inc. nor the names of its
@@ skipping 15 matching lines @@
 
 #include "core/html/HTMLContentElement.h"
 
 #include "core/HTMLNames.h"
 #include "core/css/SelectorChecker.h"
 #include "core/css/parser/CSSParser.h"
 #include "core/dom/QualifiedName.h"
 #include "core/dom/shadow/ElementShadow.h"
 #include "core/dom/shadow/ElementShadowV0.h"
 #include "core/dom/shadow/ShadowRoot.h"
+#include "core/frame/UseCounter.h"
 #include "platform/RuntimeEnabledFeatures.h"
 
 namespace blink {
 
 using namespace HTMLNames;
 
 HTMLContentElement* HTMLContentElement::create(
     Document& document,
     HTMLContentSelectFilter* filter) {
   return new HTMLContentElement(document, filter);
 }
 
 inline HTMLContentElement::HTMLContentElement(Document& document,
                                               HTMLContentSelectFilter* filter)
     : InsertionPoint(contentTag, document),
       m_shouldParseSelect(false),
       m_isValidSelector(true),
-      m_filter(filter) {}
+      m_filter(filter) {
+  UseCounter::count(document, UseCounter::HTMLContentElement);
+}
 
 HTMLContentElement::~HTMLContentElement() {}
 
 DEFINE_TRACE(HTMLContentElement) {
   visitor->trace(m_filter);
   InsertionPoint::trace(visitor);
 }
 
 void HTMLContentElement::parseSelect() {
   DCHECK(m_shouldParseSelect);
@@ skipping 62 matching lines @@
   for (const CSSSelector* selector = selectorList().first(); selector;
        selector = CSSSelectorList::next(*selector)) {
     context.selector = selector;
     if (checker.match(context))
       return true;
   }
   return false;
 }
 
 }  // namespace blink