ChromeOS: implement per-user time zone preferences.

chrome/browser/chromeos/login/screens/network_screen.cc

 // 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.
 
 #include "chrome/browser/chromeos/login/screens/network_screen.h"
 
 #include <utility>
 
 #include "base/location.h"
 #include "base/logging.h"
@@ skipping 120 matching lines @@
 std::string NetworkScreen::GetInputMethod() const {
   return input_method_;
 }
 
 void NetworkScreen::SetTimezone(const std::string& timezone_id) {
   std::string current_timezone_id;
   CrosSettings::Get()->GetString(kSystemTimezone, &current_timezone_id);
   if (current_timezone_id == timezone_id || timezone_id.empty())
     return;
   timezone_ = timezone_id;
+  g_browser_process->local_state()->SetString(prefs::kSigninScreenTimezone,
+                                              timezone_id);
   CrosSettings::Get()->SetString(kSystemTimezone, timezone_id);
 }
 
 std::string NetworkScreen::GetTimezone() const {
   return timezone_;
 }
 
 void NetworkScreen::GetConnectedWifiNetwork(std::string* out_onc_spec) {
   // Currently We can only transfer unsecured WiFi configuration from shark to
   // remora. There is no way to get password for a secured Wifi network in Cros
@@ skipping 292 matching lines @@
     observer.OnLanguageListReloaded();
 }
 
 void NetworkScreen::OnSystemTimezoneChanged() {
   std::string current_timezone_id;
   CrosSettings::Get()->GetString(kSystemTimezone, &current_timezone_id);
   GetContextEditor().SetString(kContextKeyTimezone, current_timezone_id);
 }
 
 }  // namespace chromeos