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..589f790ac2176be05cace5f51e37cb7d316e920e 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
@@ -87,10 +87,26 @@ Polymer({
       type: Boolean,
       value: false,
     },
+
+    /**
+     * Boolean flag indicatined whether per-user timezone option is enabled.

[michaelpg, 2017/05/30 22:21:23]

"indicating"

[Alexander Alekseev, 2017/07/06 06:30:29]

Done.

+     * @private
+     */
+    perUserTimezoneEnabled_: {
+      type: Boolean,
+      value: function() {
+        return loadTimeData.getBoolean('perUserTimezoneEnabled');
+      },
+    },
   },
 
+  // We need two separate observers, because prefs.settings.timezone.value is
+  // undefined when per-user timezone option is disabled, so we cannot combine
+  // all three inputs in a single observer.
   observers: [
     'maybeGetTimeZoneList_(' +
+        'prefs.settings.timezone.value, timeZoneAutoDetect_)',
+    'maybeGetTimeZoneList_(' +
         'prefs.cros.system.timezone.value, timeZoneAutoDetect_)',
   ],

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

This is much cleaner, thanks!

[Alexander Alekseev, 2017/07/06 06:30:29]

Done.

 
@@ -182,10 +198,18 @@ Polymer({
       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.perUserTimezoneEnabled_) {

[michaelpg, 2017/05/30 22:21:23]

optional: use the "if" described in the comment.

if (this.timeZoneAutoDetect_) {
  if (this.perUserTimezoneEnabled_) ...

^ the reasoning is clearer that way IMO

Or, just use a ternary for the pref name depending on the value of
perUserTimezoneEnabled_?

[Alexander Alekseev, 2017/07/06 06:30:29]

Done.

+      if (this.timeZoneAutoDetect_ &&
+          this.getPref('settings.timezone').value ==
+              this.timeZoneList_[0].value) {
+        return;
+      }
+    } else {
+      if (this.timeZoneAutoDetect_ &&
+          this.getPref('cros.system.timezone').value ==
+              this.timeZoneList_[0].value) {
+        return;
+      }
     }
 
     cr.sendWithPromise('getTimeZones').then(this.setTimeZoneList_.bind(this));
@@ -204,4 +228,16 @@ Polymer({
       };
     });
   },
+
+  /**
+   * Computes visibility of user timezone preference.
+   * @param prefUserTimezone Object pref.settings.timezone
+   * @param prefResolveValue Boolean
+   *     prefs.settings.resolve_timezone_by_geolocation.value
+   * @private
+   */
+  isUserTimeZoneSelectorHidden_: function(prefUserTimezone, prefResolveValue) {
+    return (prefUserTimezone && prefUserTimezone.controlledBy != null) ||
+        (prefResolveValue == true);
+  },
 });