cc: Use a ListContainer for DisplayItemList to reduce allocations.

cc/resources/clip_display_item.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 CC_RESOURCES_CLIP_DISPLAY_ITEM_H_
 #define CC_RESOURCES_CLIP_DISPLAY_ITEM_H_
 
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
 #include "cc/base/cc_export.h"
 #include "cc/resources/display_item.h"
 #include "third_party/skia/include/core/SkRRect.h"
 #include "ui/gfx/geometry/rect.h"
 
 class SkCanvas;
 class SkDrawPictureCallback;
 
 namespace cc {
 
 class CC_EXPORT ClipDisplayItem : public DisplayItem {
  public:
+  ClipDisplayItem();
   ~ClipDisplayItem() override;
 
-  static scoped_ptr<ClipDisplayItem> Create(
-      gfx::Rect clip_rect,
-      const std::vector<SkRRect>& rounded_clip_rects) {
-    return make_scoped_ptr(new ClipDisplayItem(clip_rect, rounded_clip_rects));
-  }
+  void SetNew(gfx::Rect clip_rect,
+              const std::vector<SkRRect>& rounded_clip_rects);
 
   void Raster(SkCanvas* canvas, SkDrawPictureCallback* callback) const override;
 
   bool IsSuitableForGpuRasterization() const override;
   int ApproximateOpCount() const override;
   size_t PictureMemoryUsage() const override;
   void AsValueInto(base::trace_event::TracedValue* array) const override;
 
  protected:
   ClipDisplayItem(gfx::Rect clip_rect,
                   const std::vector<SkRRect>& rounded_clip_rects);
 
  private:
   gfx::Rect clip_rect_;
   std::vector<SkRRect> rounded_clip_rects_;
 };
 
 class CC_EXPORT EndClipDisplayItem : public DisplayItem {
  public:
+  EndClipDisplayItem();
   ~EndClipDisplayItem() override;
 
-  static scoped_ptr<EndClipDisplayItem> Create() {
-    return make_scoped_ptr(new EndClipDisplayItem());
-  }
-
   void Raster(SkCanvas* canvas, SkDrawPictureCallback* callback) const override;
 
   bool IsSuitableForGpuRasterization() const override;
   int ApproximateOpCount() const override;
   size_t PictureMemoryUsage() const override;
   void AsValueInto(base::trace_event::TracedValue* array) const override;
-
- protected:
-  EndClipDisplayItem();
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_CLIP_DISPLAY_ITEM_H_