Revert of Back PaintRecord with PaintOpBuffer instead of SkPicture

cc/paint/skia_paint_canvas.h

 // Copyright 2017 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_PAINT_SKIA_PAINT_CANVAS_H_
 #define CC_PAINT_SKIA_PAINT_CANVAS_H_
 
 #include <memory>
 
 #include "base/compiler_specific.h"
@@ skipping 10 matching lines @@
 class PaintFlags;
 
 // A PaintCanvas derived class that passes PaintCanvas APIs through to
 // an SkCanvas.  This is more efficient than recording to a PaintRecord
 // and then playing back to an SkCanvas.
 class CC_PAINT_EXPORT SkiaPaintCanvas final : public PaintCanvas {
  public:
   explicit SkiaPaintCanvas(SkCanvas* canvas);
   explicit SkiaPaintCanvas(const SkBitmap& bitmap);
   explicit SkiaPaintCanvas(const SkBitmap& bitmap, const SkSurfaceProps& props);
+  explicit SkiaPaintCanvas(SkiaPaintCanvas&& other);
   ~SkiaPaintCanvas() override;
 
+  SkiaPaintCanvas& operator=(SkiaPaintCanvas&& other) = default;
+
   SkMetaData& getMetaData() override;
   SkImageInfo imageInfo() const override;
 
   void flush() override;
 
   int save() override;
   int saveLayer(const SkRect* bounds, const PaintFlags* flags) override;
-  int saveLayerAlpha(const SkRect* bounds, uint8_t alpha) override;
+  int saveLayerAlpha(const SkRect* bounds, U8CPU alpha) override;
 
   void restore() override;
   int getSaveCount() const override;
   void restoreToCount(int save_count) override;
   void translate(SkScalar dx, SkScalar dy) override;
   void scale(SkScalar sx, SkScalar sy) override;
   void rotate(SkScalar degrees) override;
   void concat(const SkMatrix& matrix) override;
   void setMatrix(const SkMatrix& matrix) override;
 
@@ skipping 92 matching lines @@
  private:
   SkCanvas* canvas_;
   std::unique_ptr<SkCanvas> owned_;
 
   DISALLOW_COPY_AND_ASSIGN(SkiaPaintCanvas);
 };
 
 }  // namespace cc
 
 #endif  // CC_PAINT_SKIA_PAINT_CANVAS_H_