Implement RefCountedCopyable<T>.

third_party/WebKit/Source/core/style/StyleBoxData.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 18 matching lines @@
 #include "core/style/ComputedStyleConstants.h"
 #include "platform/Length.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefCounted.h"
 
 namespace blink {
 
 // TODO(sashab): Move this into a private class on ComputedStyle, and remove
 // all methods on it, merging them into copy/creation methods on ComputedStyle
 // instead. Keep the allocation logic, only allocating a new object if needed.
-class CORE_EXPORT StyleBoxData : public RefCounted<StyleBoxData> {
+class CORE_EXPORT StyleBoxData : public RefCountedCopyable<StyleBoxData> {
  public:
   static PassRefPtr<StyleBoxData> create() {
     return adoptRef(new StyleBoxData);
   }
   PassRefPtr<StyleBoxData> copy() const {
     return adoptRef(new StyleBoxData(*this));
   }
 
   bool operator==(const StyleBoxData&) const;
   bool operator!=(const StyleBoxData& o) const { return !(*this == o); }
@@ skipping 14 matching lines @@
 
   EBoxSizing boxSizing() const { return static_cast<EBoxSizing>(m_boxSizing); }
   EBoxDecorationBreak boxDecorationBreak() const {
     return static_cast<EBoxDecorationBreak>(m_boxDecorationBreak);
   }
 
  private:
   friend class ComputedStyle;
 
   StyleBoxData();
-  StyleBoxData(const StyleBoxData&);
+  StyleBoxData(const StyleBoxData&) = default;
 
   Length m_width;
   Length m_height;
 
   Length m_minWidth;
   Length m_maxWidth;
 
   Length m_minHeight;
   Length m_maxHeight;
 
   Length m_verticalAlign;
 
   int m_zIndex;
   unsigned m_hasAutoZIndex : 1;
   unsigned m_boxSizing : 1;           // EBoxSizing
   unsigned m_boxDecorationBreak : 1;  // EBoxDecorationBreak
 };
 
 }  // namespace blink
 
 #endif  // StyleBoxData_h