[blimp] Add SkPicture caching support.

cc/test/picture_cache_model.h

+// Copyright 2016 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_TEST_PICTURE_CACHE_MODEL_H_
+#define CC_TEST_PICTURE_CACHE_MODEL_H_
+
+#include <stdint.h>
+
+#include <unordered_map>
+
+#include "base/macros.h"
+#include "third_party/skia/include/core/SkRefCnt.h"
+
+class SkPicture;
+
+namespace cc {
+
+// PictureCacheModel provides a way for sharing a cache between an engine
+// and the client. When the FakeEnginePictureCache and the ClientPictureCache
+// point to the same PictureCacheModel, the calls to AddPicture on the
+// engine make an SkPicture available through GetPicture on the client.
+class PictureCacheModel {
+ public:
+  PictureCacheModel();
+  ~PictureCacheModel();
+
+  void AddPicture(const SkPicture* picture);
+
+  sk_sp<const SkPicture> GetPicture(uint32_t unique_id);
+
+ private:
+  std::unordered_map<uint32_t, sk_sp<const SkPicture>> pictures_;
+
+  DISALLOW_COPY_AND_ASSIGN(PictureCacheModel);
+};
+
+}  // namespace cc
+
+#endif  // CC_TEST_PICTURE_CACHE_MODEL_H_