Update from https://crrev.com/306655

cc/resources/transparency_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_TRANSPARENCY_DISPLAY_ITEM_H_
+#define CC_RESOURCES_TRANSPARENCY_DISPLAY_ITEM_H_
+
+#include "base/memory/scoped_ptr.h"
+#include "cc/base/cc_export.h"
+#include "cc/resources/display_item.h"
+#include "skia/ext/refptr.h"
+#include "third_party/skia/include/core/SkXfermode.h"
+#include "ui/gfx/geometry/rect_f.h"
+
+class SkCanvas;
+class SkDrawPictureCallback;
+
+namespace cc {
+
+class CC_EXPORT TransparencyDisplayItem : public DisplayItem {
+ public:
+  virtual ~TransparencyDisplayItem();
+
+  static scoped_ptr<TransparencyDisplayItem> Create(
+      float opacity,
+      SkXfermode::Mode blend_mode) {
+    return make_scoped_ptr(new TransparencyDisplayItem(opacity, blend_mode));
+  }
+
+  void Raster(SkCanvas* canvas, SkDrawPictureCallback* callback) const override;
+
+  bool IsSuitableForGpuRasterization() const override;
+  int ApproximateOpCount() const override;
+  size_t PictureMemoryUsage() const override;
+
+ protected:
+  TransparencyDisplayItem(float opacity, SkXfermode::Mode blend_mode);
+
+ private:
+  float opacity_;
+  SkXfermode::Mode blend_mode_;
+};
+
+class CC_EXPORT EndTransparencyDisplayItem : public DisplayItem {
+ public:
+  virtual ~EndTransparencyDisplayItem();
+
+  static scoped_ptr<EndTransparencyDisplayItem> Create() {
+    return make_scoped_ptr(new EndTransparencyDisplayItem());
+  }
+
+  void Raster(SkCanvas* canvas, SkDrawPictureCallback* callback) const override;
+
+  bool IsSuitableForGpuRasterization() const override;
+  int ApproximateOpCount() const override;
+  size_t PictureMemoryUsage() const override;
+
+ protected:
+  EndTransparencyDisplayItem();
+};
+
+}  // namespace cc
+
+#endif  // CC_RESOURCES_TRANSPARENCY_DISPLAY_ITEM_H_