[Slimming Paint] Blink-side contiguous allocation of display items.

Source/platform/graphics/paint/ClipDisplayItem.h

 // Copyright 2014 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 ClipDisplayItem_h
 #define ClipDisplayItem_h
 
 #include "SkRegion.h"
 #include "platform/PlatformExport.h"
 #include "platform/geometry/FloatRoundedRect.h"
@@ skipping 15 matching lines @@
     ClipDisplayItem(const DisplayItemClientWrapper& client, Type type, const IntRect& clipRect, SkRegion::Op operation = SkRegion::kIntersect_Op)
         : PairedBeginDisplayItem(client, type)
         , m_clipRect(clipRect)
         , m_operation(operation)
     {
         ASSERT(isClipType(type));
     }
 
     virtual void replay(GraphicsContext&) override;
     virtual void appendToWebDisplayItemList(WebDisplayItemList*) const override;
+    virtual void appendByMoving(DisplayItems&) override;
 
     Vector<FloatRoundedRect>& roundedRectClips() { return m_roundedRectClips; }
 
 private:
 #ifndef NDEBUG
     virtual void dumpPropertiesAsDebugString(WTF::StringBuilder&) const override;
 #endif
     IntRect m_clipRect;
     Vector<FloatRoundedRect> m_roundedRectClips;
     SkRegion::Op m_operation;
 };
 
 class PLATFORM_EXPORT EndClipDisplayItem : public PairedEndDisplayItem {
     WTF_MAKE_FAST_ALLOCATED(EndClipDisplayItem);
 public:
     static PassOwnPtr<EndClipDisplayItem> create(const DisplayItemClientWrapper& client, Type type)
     {
         return adoptPtr(new EndClipDisplayItem(client, type));
     }
 
     EndClipDisplayItem(const DisplayItemClientWrapper& client, Type type)
         : PairedEndDisplayItem(client, type)
     {
         ASSERT(isEndClipType(type));
     }
 
     virtual void replay(GraphicsContext&) override;
     virtual void appendToWebDisplayItemList(WebDisplayItemList*) const override;
+    virtual void appendByMoving(DisplayItems&) override;
 
 private:
 #if ENABLE(ASSERT)
     virtual bool isEndAndPairedWith(DisplayItem::Type otherType) const override final { return DisplayItem::isClipType(otherType); }
 #endif
 };
 
 } // namespace blink
 
 #endif // ClipDisplayItem_h