Add serialization/deserialization for FakePictureLayer for testing.

cc/test/remote_client_layer_factory.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_REMOTE_CLIENT_LAYER_FACTORY_H_
 #define CC_TEST_REMOTE_CLIENT_LAYER_FACTORY_H_
 
 #include "base/macros.h"
 #include "cc/blimp/layer_factory.h"
 
 namespace cc {
 
 // An implementation of LayerFactory for tests that ensures that the layer id
 // for layers created on the client matches the ids of the corresponding layers
 // on the engine.
 class RemoteClientLayerFactory : public LayerFactory {
  public:
   RemoteClientLayerFactory();
   ~RemoteClientLayerFactory() override;
 
   // LayerFactory implementation.
   scoped_refptr<Layer> CreateLayer(int engine_layer_id) override;
   scoped_refptr<PictureLayer> CreatePictureLayer(
       int engine_layer_id,
       ContentLayerClient* content_layer_client) override;
+  scoped_refptr<PictureLayer> CreateFakePictureLayer(
+      int engine_layer_id,
+      ContentLayerClient* content_layer_client) override;
   scoped_refptr<SolidColorScrollbarLayer> CreateSolidColorScrollbarLayer(
       int engine_layer_id,
       ScrollbarOrientation orientation,
       int thumb_thickness,
       int track_start,
       bool is_left_side_vertical_scrollbar,
       int scroll_layer_id) override;
 };
 
 }  // namespace cc
 
 #endif  // CC_TEST_REMOTE_CLIENT_LAYER_FACTORY_H_