Add support for a virtual display on ChromeOS

ui/display/display.gyp

 # Copyright 2014 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.
 
 {
   'variables': {
     'chromium_code': 1,
   },
   'targets': [
     {
@@ skipping 33 matching lines @@
         'DISPLAY_IMPLEMENTATION',
       ],
       'sources': [
         # Note: file list duplicated in GN build.
         'chromeos/configure_displays_task.cc',
         'chromeos/configure_displays_task.h',
         'chromeos/display_configurator.cc',
         'chromeos/display_configurator.h',
         'chromeos/display_util.cc',
         'chromeos/display_util.h',
+        'chromeos/display_snapshot_virtual.cc',
+        'chromeos/display_snapshot_virtual.h',
         'chromeos/ozone/display_configurator_ozone.cc',
         'chromeos/update_display_configuration_task.cc',
         'chromeos/update_display_configuration_task.h',
         'chromeos/x11/display_configurator_x11.cc',
         'chromeos/x11/display_mode_x11.cc',
         'chromeos/x11/display_mode_x11.h',
         'chromeos/x11/display_snapshot_x11.cc',
         'chromeos/x11/display_snapshot_x11.h',
         'chromeos/x11/display_util_x11.cc',
         'chromeos/x11/display_util_x11.h',
@@ skipping 114 matching lines @@
       ],
     },
     {
       # GN version: //ui/display:display_unittests
       'target_name': 'display_unittests',
       'type': 'executable',
       'dependencies': [
         '../../base/base.gyp:run_all_unittests',
         '../../testing/gtest.gyp:gtest',
         '../../ui/gfx/gfx.gyp:gfx_geometry',
+        '../../ui/gfx/gfx.gyp:gfx_test_support',
         'display_util',
       ],
       'include_dirs': [
         '../..',
       ],
       'sources': [
         'chromeos/configure_displays_task_unittest.cc',
         'chromeos/display_configurator_unittest.cc',
         'chromeos/update_display_configuration_task_unittest.cc',
         'chromeos/x11/display_util_x11_unittest.cc',
         'chromeos/x11/native_display_event_dispatcher_x11_unittest.cc',
         'util/display_util_unittest.cc',
         'util/edid_parser_unittest.cc',
       ],
       'conditions': [
         ['chromeos == 1', {
           'dependencies': [
             'display',
             'display_test_support',
             'display_test_util',
             'display_types',
           ],
         }],
       ],
     },
   ],
 }