Make FrameCaret contains CaretBase instead of deriving from it

third_party/WebKit/Source/core/editing/CaretBase.h

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef CaretBase_h
 #define CaretBase_h
 
-#include "core/CoreExport.h"
 #include "core/editing/VisiblePosition.h"
 #include "platform/geometry/IntRect.h"
 #include "platform/geometry/LayoutRect.h"
 #include "platform/graphics/paint/DisplayItem.h"
 #include "wtf/Noncopyable.h"
 
 namespace blink {
 
-class DisplayItemClient;
 class GraphicsContext;
 class LayoutBlock;
 
-class CORE_EXPORT CaretBase : public GarbageCollectedFinalized<CaretBase>,
-                              public DisplayItemClient {
+class CaretBase final : public DisplayItemClient {
   WTF_MAKE_NONCOPYABLE(CaretBase);
 
  public:
   CaretBase();
   virtual ~CaretBase();
 
   void invalidateCaretRect(Node*, const LayoutRect&);
   // Creating VisiblePosition causes synchronous layout so we should use the
   // PositionWithAffinity version if possible.
   // A position in HTMLTextFromControlElement is a typical example.
   static LayoutRect computeCaretRect(const PositionWithAffinity& caretPosition);
 
   // TODO(yosin): We should move |computeCaretRect()| with |VisiblePosition| to
   // "FrameCaret.cpp" as static file local function.
   static LayoutRect computeCaretRect(const VisiblePosition& caretPosition);
 
   // TODO(yosin): We should move |absoluteBoundsForLocalRect()| with
   // |VisiblePosition| to "FrameCaret.cpp" as static file local function.
-  IntRect absoluteBoundsForLocalRect(Node*, const LayoutRect&) const;
+  static IntRect absoluteBoundsForLocalRect(Node*, const LayoutRect&);
 
   // TODO(yosin): We should move |shouldRepaintCaret()| to "FrameCaret.cpp" as
   // static file local function.
-  bool shouldRepaintCaret(Node&) const;
+  static bool shouldRepaintCaret(Node&);
+  // TODO(yosin): We should make |paintCaret()| to non-static member and get rid
+  // |DisplayItemClient| parameter.
   static void paintCaret(Node*,
                          GraphicsContext&,
                          const DisplayItemClient&,
                          const LayoutRect& caretLocalRect,
                          const LayoutPoint&,
                          DisplayItem::Type);
 
   static LayoutBlock* caretLayoutObject(Node*);
   void invalidateLocalCaretRect(Node*, const LayoutRect&);
 
   // DisplayItemClient methods.
-  LayoutRect visualRect() const override;
+  LayoutRect visualRect() const final;
   String debugName() const final;
 
-  DECLARE_VIRTUAL_TRACE();
-
  private:
   LayoutRect m_visualRect;
 };
 
 }  // namespace blink
 
 #endif  // CaretBase_h