Add serialization/deserialization for FakePictureLayer for testing.

cc/proto/layer.proto

 // Copyright 2015 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.
 
 syntax = "proto2";
 
 import "display_item.proto";
 import "layer_position_constraint.proto";
 import "layer_sticky_position_constraint.proto";
 import "point3f.proto";
@@ skipping 15 matching lines @@
 message LayerNode {
   // Identifies the type of cc:Layer a LayerNode represents. It is used to
   // facilitate reconstruction of a Layer of the correct type on the client.
   enum Type {
     UNKNOWN = 0;
     LAYER = 1;
     PICTURE_LAYER = 2;
     HEADS_UP_DISPLAY_LAYER = 3;
     SOLID_COLOR_SCROLLBAR_LAYER = 4;
 
+    // Layer Types for testing only.
+    FAKE_PICTURE_LAYER = 5;
+
     // TODO(nyquist): Add the rest of the necessary LayerTypes.
   };
 
   // required
   optional int32 id = 1;
   // required
   optional Type type = 2;
   optional int32 parent_id = 3;
   // A List of all the children of the current LayerNode.
   repeated LayerNode children = 4;
@@ skipping 122 matching lines @@
     HORIZONTAL = 0;
     VERTICAL = 1;
   };
 
   optional int32 scroll_layer_id = 1;
   optional int32 thumb_thickness = 2;
   optional int32 track_start = 3;
   optional bool is_left_side_vertical_scrollbar = 4;
   optional ScrollbarOrientation orientation = 5;
 }