Make NinePieceImageData use RefCountedCopyable.

third_party/WebKit/Source/core/style/NinePieceImage.cpp

 /*
  * 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, 2013 Apple Inc. All rights
  * reserved.
  *
  * 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 51 matching lines @@
       image_slices(Length(100, kPercent),
                    Length(100, kPercent),
                    Length(100, kPercent),
                    Length(100, kPercent)),
       border_slices(1.0, 1.0, 1.0, 1.0),
       outset(Length(0, kFixed),
              Length(0, kFixed),
              Length(0, kFixed),
              Length(0, kFixed)) {}
 
-NinePieceImageData::NinePieceImageData(const NinePieceImageData& other)
-    : RefCounted<NinePieceImageData>(),
-      fill(other.fill),
-      horizontal_rule(other.horizontal_rule),
-      vertical_rule(other.vertical_rule),
-      image(other.image),
-      image_slices(other.image_slices),
-      border_slices(other.border_slices),
-      outset(other.outset) {}
-
 bool NinePieceImageData::operator==(const NinePieceImageData& other) const {
   return DataEquivalent(image, other.image) &&
          image_slices == other.image_slices && fill == other.fill &&
          border_slices == other.border_slices && outset == other.outset &&
          horizontal_rule == other.horizontal_rule &&
          vertical_rule == other.vertical_rule;
 }
 
 }  // namespace blink