Added a timezone policy and pyauto tests for it.

chrome/browser/policy/proto/chrome_device_policy.proto

 // Copyright (c) 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.
 
 syntax = "proto2";
 
 option optimize_for = LITE_RUNTIME;
 
 package enterprise_management;
 
@@ skipping 188 matching lines @@
   // Bluetooth and Cellular at the moment.
   repeated ConnectionType allowed_connection_types = 5;
 }
 
 message StartUpUrlsProto {
   // Specifies the URLs to be loaded on login to the anonymous account used if
   // the device is in RETAIL mode.
   repeated string start_up_urls = 1;
 }
 
+message SystemTimezoneProto {
+  // Specifies the timezone which is applied if this value is provided. 
+  optional string timezone = 1;
+}
+
 message ChromeDeviceSettingsProto {
   optional DevicePolicyRefreshRateProto device_policy_refresh_rate = 1;
   optional UserWhitelistProto user_whitelist = 2;
   optional GuestModeEnabledProto guest_mode_enabled = 3;
   optional DeviceProxySettingsProto device_proxy_settings = 4;
   optional CameraEnabledProto camera_enabled = 5;
   optional ShowUserNamesOnSigninProto show_user_names = 6;
   optional DataRoamingEnabledProto data_roaming_enabled = 7;
   optional AllowNewUsersProto allow_new_users = 8;
   optional MetricsEnabledProto metrics_enabled = 9;
   optional ReleaseChannelProto release_channel = 10;
   optional DeviceOpenNetworkConfigurationProto open_network_configuration = 11;
   optional DeviceReportingProto device_reporting = 12;
   optional EphemeralUsersEnabledProto ephemeral_users_enabled = 13;
   optional AppPackProto app_pack = 14;
   optional ForcedLogoutTimeoutsProto forced_logout_timeouts = 15;
   optional ScreenSaverProto login_screen_saver = 16;
   optional AutoUpdateSettingsProto auto_update_settings = 17;
   optional StartUpUrlsProto start_up_urls = 18;
   optional PinnedAppsProto pinned_apps = 19;
+  optional SystemTimezoneProto system_timezone = 20;
 }