[blimp] Add SkPicture caching support.

cc/test/skia_common.cc

 // Copyright 2012 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.
 
 #include "cc/test/skia_common.h"
 
 #include <stddef.h>
 
 #include "cc/playback/display_item_list.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkImageGenerator.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/skia_util.h"
 
 namespace cc {
 
 namespace {
 
 class TestImageGenerator : public SkImageGenerator {
  public:
   explicit TestImageGenerator(const SkImageInfo& info)
       : SkImageGenerator(info) {}
 };
 
 }  // anonymous namespace
 
 void DrawDisplayList(unsigned char* buffer,
                      const gfx::Rect& layer_rect,
-                     scoped_refptr<DisplayItemList> list) {
+                     scoped_refptr<const DisplayItemList> list) {
   SkImageInfo info =
       SkImageInfo::MakeN32Premul(layer_rect.width(), layer_rect.height());
   SkBitmap bitmap;
   bitmap.installPixels(info, buffer, info.minRowBytes());
   SkCanvas canvas(bitmap);
   canvas.clipRect(gfx::RectToSkRect(layer_rect));
   list->Raster(&canvas, NULL, gfx::Rect(), 1.0f);
 }
 
 bool AreDisplayListDrawingResultsSame(const gfx::Rect& layer_rect,
-                                      scoped_refptr<DisplayItemList> list_a,
-                                      scoped_refptr<DisplayItemList> list_b) {
+                                      const DisplayItemList* list_a,
+                                      const DisplayItemList* list_b) {
   const size_t pixel_size = 4 * layer_rect.size().GetArea();
 
   std::unique_ptr<unsigned char[]> pixels_a(new unsigned char[pixel_size]);
   std::unique_ptr<unsigned char[]> pixels_b(new unsigned char[pixel_size]);
   memset(pixels_a.get(), 0, pixel_size);
   memset(pixels_b.get(), 0, pixel_size);
   DrawDisplayList(pixels_a.get(), layer_rect, list_a);
   DrawDisplayList(pixels_b.get(), layer_rect, list_b);
 
   return !memcmp(pixels_a.get(), pixels_b.get(), pixel_size);
 }
 
 sk_sp<SkImage> CreateDiscardableImage(const gfx::Size& size) {
   return SkImage::MakeFromGenerator(new TestImageGenerator(
       SkImageInfo::MakeN32Premul(size.width(), size.height())));
 }
 
 }  // namespace cc