Add a tuple of name, local name for hashing custom element definitions.

third_party/WebKit/Source/core/dom/custom/CustomElementDefinition.h

 // Copyright 2016 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.
 
 #ifndef CustomElementDefinition_h
 #define CustomElementDefinition_h
 
 #include "bindings/core/v8/ScopedPersistent.h"
+#include "core/dom/custom/CustomElementDescriptor.h"
 #include "core/dom/custom/CustomElementsRegistry.h"
 #include "platform/heap/Handle.h"
 #include "v8.h"
-#include "wtf/text/AtomicString.h"
 
 namespace blink {
 
 class CustomElementDefinition final
     : public GarbageCollectedFinalized<CustomElementDefinition> {
 public:
     CustomElementDefinition(
         CustomElementsRegistry*,
         CustomElementsRegistry::Id,
-        const AtomicString& localName);
+        const CustomElementDescriptor&);
 
     CustomElementsRegistry::Id id() const { return m_id; }
-    const AtomicString& localName() const { return m_localName; }
+    const CustomElementDescriptor& descriptor() { return m_descriptor; }
     v8::Local<v8::Object> prototype(ScriptState*) const;
 
     DEFINE_INLINE_TRACE()
     {
         visitor->trace(m_registry);
     }
 
 private:
     Member<CustomElementsRegistry> m_registry;
     CustomElementsRegistry::Id m_id;
-    AtomicString m_localName;
+    CustomElementDescriptor m_descriptor;
 };
 
 } // namespace blink
 
 #endif // CustomElementDefinition_h