Switch to direct use of OwnerSettingsServiceChromeOS::Set() in tests.

chrome/chrome_tests_unit.gypi

 # Copyright 2012 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': {
     'chrome_unit_tests_sources': [
       '../components/autofill/content/renderer/test_password_autofill_agent.cc',
       '../components/autofill/content/renderer/test_password_autofill_agent.h',
       '../components/autofill/content/renderer/test_password_generation_agent.cc',
       '../components/autofill/content/renderer/test_password_generation_agent.h',
@@ skipping 1283 matching lines @@
       'browser/chromeos/power/power_prefs_unittest.cc',
       'browser/chromeos/power/renderer_freezer_unittest.cc',
       'browser/chromeos/preferences_unittest.cc',
       'browser/chromeos/profiles/profile_list_chromeos_unittest.cc',
       'browser/chromeos/proxy_config_service_impl_unittest.cc',
       'browser/chromeos/session_length_limiter_unittest.cc',
       'browser/chromeos/settings/cros_settings_unittest.cc',
       'browser/chromeos/settings/device_oauth2_token_service_unittest.cc',
       'browser/chromeos/settings/device_settings_provider_unittest.cc',
       'browser/chromeos/settings/device_settings_service_unittest.cc',
+      'browser/chromeos/settings/scoped_cros_settings_test_helper.cc',
+      'browser/chromeos/settings/scoped_cros_settings_test_helper.h',
       'browser/chromeos/settings/session_manager_operation_unittest.cc',
       'browser/chromeos/settings/shutdown_policy_handler_unittest.cc',
       'browser/chromeos/settings/stub_cros_settings_provider_unittest.cc',
       'browser/chromeos/system/automatic_reboot_manager_unittest.cc',
       'browser/chromeos/system/device_disabling_manager_unittest.cc',
       'browser/chromeos/ui/accessibility_focus_ring_controller_unittest.cc',
       'browser/chromeos/ui/idle_app_name_notification_view_unittest.cc',
       'browser/download/notification/download_notification_item_unittest.cc',
       'browser/extensions/api/enterprise_platform_keys_private/enterprise_platform_keys_private_api_unittest.cc',
       'browser/extensions/api/log_private/syslog_parser_unittest.cc',
@@ skipping 1463 matching lines @@
               'dependencies': [
                 '../tools/xdisplaycheck/xdisplaycheck.gyp:xdisplaycheck',
               ],
             }],
           ],
         },
       ],
     }],
   ],  # 'conditions'
 }