cc/blimp: Add (de)-serialization for PictureLayer and ScrollbarLayer.

cc/blimp/layer_tree_host_remote.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_BLIMP_LAYER_TREE_HOST_REMOTE_H_
 #define CC_BLIMP_LAYER_TREE_HOST_REMOTE_H_
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "cc/base/cc_export.h"
 #include "cc/blimp/remote_compositor_bridge_client.h"
 #include "cc/debug/layer_tree_debug_state.h"
 #include "cc/surfaces/surface_sequence_generator.h"
 #include "cc/trees/layer_tree_host.h"
 #include "cc/trees/layer_tree_settings.h"
 #include "cc/trees/swap_promise_manager.h"
 
 namespace base {
 class SingleThreadTaskRunner;
 }  // namespace base
 
 namespace cc {
 namespace proto {
 class LayerTreeHost;
 }  // namespace proto
 
 class AnimationHost;
+class EnginePictureCache;
+class ImageSerializationProcessor;
 class RemoteCompositorBridge;
 class LayerTreeHostClient;
 
 class CC_EXPORT LayerTreeHostRemote : public LayerTreeHost,
                                       public RemoteCompositorBridgeClient {
  public:
   struct CC_EXPORT InitParams {
     LayerTreeHostClient* client = nullptr;
     scoped_refptr<base::SingleThreadTaskRunner> main_task_runner;
     std::unique_ptr<AnimationHost> animation_host;
     std::unique_ptr<RemoteCompositorBridge> remote_compositor_bridge;
+    std::unique_ptr<EnginePictureCache> engine_picture_cache;
     LayerTreeSettings const* settings = nullptr;
 
     InitParams();
     ~InitParams();
   };
 
   explicit LayerTreeHostRemote(InitParams* params);
   ~LayerTreeHostRemote() override;
 
   // LayerTreeHost implementation.
@@ skipping 82 matching lines @@
   // Set to the pipeline stage requested for the next BeginMainFrame.
   FramePipelineStage requested_pipeline_stage_for_next_frame_ =
       FramePipelineStage::NONE;
 
   LayerTreeHostClient* client_;
   std::unique_ptr<TaskRunnerProvider> task_runner_provider_;
 
   // The RemoteCompositorBridge used to submit frame updates to the client.
   std::unique_ptr<RemoteCompositorBridge> remote_compositor_bridge_;
 
+  // Used to cache SkPictures sent with DisplayLists to the client.
+  // TODO(khushalsagar): Restructure to give this with the CompositorProtoState
+  // and eliminate this abstraction. See crbug.com/648442.
+  std::unique_ptr<EnginePictureCache> engine_picture_cache_;
+
   LayerTreeSettings settings_;
   LayerTreeDebugState debug_state_;
 
   // The LayerTree holds the root layer and other state on the engine.
   std::unique_ptr<LayerTree> layer_tree_;
 
   SwapPromiseManager swap_promise_manager_;
   SurfaceSequenceGenerator surface_sequence_generator_;
 
   base::WeakPtr<InputHandler> input_handler_weak_ptr_;
 
   base::WeakPtrFactory<LayerTreeHostRemote> weak_factory_;
 };
 
 }  // namespace cc
 
 #endif  // CC_BLIMP_LAYER_TREE_HOST_REMOTE_H_