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"
 #include "base/strings/string16.h"
 #include "base/strings/string_number_conversions.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/base/locale_util.h"
 #include "chrome/browser/chromeos/customization/customization_document.h"
 #include "chrome/browser/chromeos/login/help_app_launcher.h"
 #include "chrome/browser/chromeos/login/helper.h"
 #include "chrome/browser/chromeos/login/screen_manager.h"
 #include "chrome/browser/chromeos/login/screens/base_screen_delegate.h"
 #include "chrome/browser/chromeos/login/screens/network_view.h"
 #include "chrome/browser/chromeos/login/ui/input_events_blocker.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
+#include "chrome/browser/chromeos/system/timezone_util.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/ui/webui/chromeos/login/l10n_util.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/grit/chromium_strings.h"
 #include "chrome/grit/generated_resources.h"
 #include "chromeos/network/network_handler.h"
 #include "chromeos/network/network_state_handler.h"
 #include "components/prefs/pref_service.h"
 #include "content/public/browser/browser_thread.h"
 #include "ui/base/l10n/l10n_util.h"
@@ skipping 92 matching lines @@
 
 std::string NetworkScreen::GetApplicationLocale() {
   return g_browser_process->GetApplicationLocale();
 }
 
 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;
-  CrosSettings::Get()->SetString(kSystemTimezone, timezone_id);
+  if (system::PerUserTimezoneEnabled()) {
+    if (timezone_id.empty())
+      return;
+
+    timezone_ = timezone_id;
+    chromeos::system::SetSystemAndSigninScreenTimezone(timezone_id);

[stevenjb, 2017/05/25 22:13:06]

Could we make this do the test and call CrosSettings::Get()->SetString if
system::PerUserTimezoneEnabled() is false instead?

[Alexander Alekseev, 2017/05/29 21:10:23]

SetSystemAndSigninScreenTimezone() is setting timezone directly (via
system::TimezoneSettings). CrosSettings interface is designed to be used for UI
API and does additional checks.

If I make this change, CrosSettings API will also be used in the other places,
where it could be wrong. On the contrary, replacing CrosSettings with
system::TimezoneSettings call will not exactly mimic the old behavior here.

[stevenjb, 2017/05/30 16:47:18]

I was suggesting:

SetSystemAndSigninScreenTimezone(const std::string& timezone) {
  if (!PerUserTimezoneEnabled()) {
    ... execute lines 143-149 from this file and return
  }
}

And remove the if() in line 136. timezone_util already accesses CrosSettings so
it wouldn't add any new dependencies there and it would simplify this UI code.
It doesn't look like that would impact any other calls to
SetSystemAndSigninScreenTimezone(), but perhaps I missed a call in which case I
guess this is fine as-is.

[Alexander Alekseev, 2017/07/06 06:30:28]

You're righ. Even more, SetSystemAndSigninScreenTimezone() seems to do exactly
the same as lines 143-148 now, so we can simply drop PerUserTimezoneEnabled()
check here.

+  } else {
+    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;
+    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
   // for security reasons.
@@ skipping 290 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