ChromeOS: implement per-user time zone preferences.

chrome/browser/resources/settings/date_time_page/date_time_page.js

Index: chrome/browser/resources/settings/date_time_page/date_time_page.js
diff --git a/chrome/browser/resources/settings/date_time_page/date_time_page.js b/chrome/browser/resources/settings/date_time_page/date_time_page.js
index 3b004f22eabfd72b0a33f42437fe37b9ca52e093..ef37894763604b37d0a7b6a052b2c531189e41aa 100644
--- a/chrome/browser/resources/settings/date_time_page/date_time_page.js
+++ b/chrome/browser/resources/settings/date_time_page/date_time_page.js
@@ -90,7 +90,9 @@ Polymer({
   },
 
   observers: [
-    'maybeGetTimeZoneList_(' +
+    'maybeGetTimeZoneListPerUser_(' +
+        'prefs.settings.timezone.value, timeZoneAutoDetect_)',
+    'maybeGetTimeZoneListPerSystem_(' +
         'prefs.cros.system.timezone.value, timeZoneAutoDetect_)',
   ],
 
@@ -174,23 +176,53 @@ Polymer({
 
   /**
    * Fetches the list of time zones if necessary.
+   * @param {boolean=} perUserTimeZoneMode Expected value of per-user time zone.
    * @private
    */
-  maybeGetTimeZoneList_: function() {
+  maybeGetTimeZoneList_: function(perUserTimeZoneMode) {
+    if (typeof(perUserTimeZoneMode) !== 'undefined') {
+      /* This method is called as observer. Skip if if current mode does not
+       * match expected.
+       */
+      if (perUserTimeZoneMode !=
+          this.getPref('cros.flags.per_user_timezone_enabled').value) {
+        return;
+      }
+    }
     // Only fetch the list once.
     if (this.timeZoneList_.length > 1 || !CrSettingsPrefs.isInitialized)
       return;
 
     // If auto-detect is enabled, we only need the current time zone.
-    if (this.timeZoneAutoDetect_ &&
-        this.getPref('cros.system.timezone').value ==
-            this.timeZoneList_[0].value) {
-      return;
+    if (this.timeZoneAutoDetect_) {
+      var isPerUserTimezone =
+          this.getPref('cros.flags.per_user_timezone_enabled').value;
+      if (this.timeZoneList_[0].value ==
+          (isPerUserTimezone ? this.getPref('settings.timezone').value :
+                               this.getPref('cros.system.timezone').value)) {
+        return;
+      }
     }
 
     cr.sendWithPromise('getTimeZones').then(this.setTimeZoneList_.bind(this));
   },
 
+  /**
+   * Prefs observer for Per-user time zone enabled mode.
+   * @private
+   */
+  maybeGetTimeZoneListPerUser_: function() {
+    this.maybeGetTimeZoneList_(true);
+  },
+
+  /**
+   * Prefs observer for Per-user time zone disabled mode.
+   * @private
+   */
+  maybeGetTimeZoneListPerSystem_: function() {
+    this.maybeGetTimeZoneList_(false);
+  },
+
   /**
    * Converts the C++ response into an array of menu options.
    * @param {!Array<!Array<string>>} timeZones C++ time zones response.
@@ -204,4 +236,17 @@ Polymer({
       };
     });
   },
+
+  /**
+   * Computes visibility of user timezone preference.
+   * @param {?chrome.settingsPrivate.PrefObject} prefUserTimezone
+   *     pref.settings.timezone
+   * @param {boolean} prefResolveValue
+   *     prefs.settings.resolve_timezone_by_geolocation.value
+   * @private
+   */
+  isUserTimeZoneSelectorHidden_: function(prefUserTimezone, prefResolveValue) {
+    return (prefUserTimezone && prefUserTimezone.controlledBy != null) ||
+        prefResolveValue;
+  },
 });