Add SurfaceReference class.

cc/ipc/BUILD.gn

 # 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.
 
 import("//build/config/ui.gni")
 import("//cc/cc.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 
 cc_component("ipc") {
   output_name = "cc_ipc"
@@ skipping 36 matching lines @@
     "frame_sink_id.mojom",
     "local_frame_id.mojom",
     "mojo_compositor_frame_sink.mojom",
     "quads.mojom",
     "render_pass.mojom",
     "render_pass_id.mojom",
     "returned_resource.mojom",
     "selection.mojom",
     "shared_quad_state.mojom",
     "surface_id.mojom",
+    "surface_reference.mojom",
     "surface_sequence.mojom",
     "transferable_resource.mojom",
   ]
 
   public_deps = [
     "//gpu/ipc/common:interfaces",
     "//mojo/common:common_custom_types",
     "//skia/public/interfaces",
     "//ui/events/mojo:interfaces",
     "//ui/gfx/geometry/mojo",
@@ skipping 37 matching lines @@
     "frame_sink_id_struct_traits.h",
     "local_frame_id_struct_traits.h",
     "quads_struct_traits.cc",
     "quads_struct_traits.h",
     "render_pass_id_struct_traits.h",
     "render_pass_struct_traits.cc",
     "render_pass_struct_traits.h",
     "selection_struct_traits.h",
     "shared_quad_state_struct_traits.h",
     "surface_id_struct_traits.h",
+    "surface_reference_struct_traits.h",
     "surface_sequence_struct_traits.h",
     "transferable_resource_struct_traits.cc",
     "transferable_resource_struct_traits.h",
   ]
   public_deps = [
     ":interfaces_shared_cpp_sources",
     "//base",
     "//cc",
     "//cc/surfaces:surface_id",
     "//gpu/ipc/common:struct_traits",
     "//mojo/common:struct_traits",
     "//skia/public/interfaces:struct_traits",
     "//ui/events:events_base",
     "//ui/events/mojo:struct_traits",
     "//ui/gfx",
     "//ui/gfx:selection_bound",
     "//ui/gfx/geometry/mojo:struct_traits",
     "//ui/gfx/mojo:struct_traits",
   ]
 }