Implement callback reactions for Custom Elements V1

third_party/WebKit/Source/core/dom/custom/CustomElementUpgradeReaction.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 CustomElementUpgradeReaction_h
 #define CustomElementUpgradeReaction_h
 
 #include "core/CoreExport.h"
 #include "core/dom/custom/CustomElementReaction.h"
 #include "platform/heap/Handle.h"
 #include "wtf/Noncopyable.h"
 
 namespace blink {
 
-class CustomElementDefinition;
 class Element;
 
 class CORE_EXPORT CustomElementUpgradeReaction final
     : public CustomElementReaction {
     WTF_MAKE_NONCOPYABLE(CustomElementUpgradeReaction);
 public:
     CustomElementUpgradeReaction(CustomElementDefinition*);
-    ~CustomElementUpgradeReaction() override;
-    DECLARE_VIRTUAL_TRACE();
+
 private:
     void invoke(Element*) override;
-
-    Member<CustomElementDefinition> m_definition;
 };
 
 } // namespace blink
 
 #endif // CustomElementUpgradeReaction_h