chromeos: changes how DisplayManagerObservers are notified

ash/mus/BUILD.gn

 # 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.
 
 import("//build/config/ui.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 import("//services/service_manager/public/cpp/service.gni")
 import("//services/service_manager/public/service_manifest.gni")
 import("//tools/grit/repack.gni")
 
@@ skipping 14 matching lines @@
     "bridge/immersive_handler_factory_mus.cc",
     "bridge/immersive_handler_factory_mus.h",
     "bridge/shell_port_mash.cc",
     "bridge/shell_port_mash.h",
     "bridge/workspace_event_handler_mus.cc",
     "bridge/workspace_event_handler_mus.h",
     "context_menu_mus.cc",
     "context_menu_mus.h",
     "disconnected_app_handler.cc",
     "disconnected_app_handler.h",
+    "display_synchronizer.cc",
+    "display_synchronizer.h",
     "drag_window_resizer.cc",
     "drag_window_resizer.h",
     "frame/detached_title_area_renderer.cc",
     "frame/detached_title_area_renderer.h",
     "keyboard_ui_mus.cc",
     "keyboard_ui_mus.h",
     "move_event_handler.cc",
     "move_event_handler.h",
     "network_connect_delegate_mus.cc",
     "network_connect_delegate_mus.h",
@@ skipping 187 matching lines @@
     "//ui/views/mus",
   ]
 
   data_deps = [
     ":mus",
     "//mash/quick_launch",
   ]
 
   defines = [ "NOTIMPLEMENTED_POLICY=5" ]
 }