events: Fix timezone realm-time sync and add test.

zerver/lib/events.py

@@ -153,9 +153,8 @@ def fetch_initial_state_data(user_profile, event_types, queue_id,
         state['twenty_four_hour_time'] = user_profile.twenty_four_hour_time
         state['left_side_userlist'] = user_profile.left_side_userlist
         state['emoji_alt_code'] = user_profile.emoji_alt_code
-
-        default_language = user_profile.default_language
-        state['default_language'] = default_language
+        state['timezone'] = user_profile.timezone
+        state['default_language'] = user_profile.default_language
 
     if want('update_global_notifications'):
         state['enable_stream_desktop_notifications'] = user_profile.enable_stream_desktop_notifications
@@ -386,6 +385,8 @@ def name(sub):
             state['emoji_alt_code'] = event["setting"]
         if event['setting_name'] == 'default_language':
             state['default_language'] = event["setting"]
+        if event['setting_name'] == 'timezone':
+            state['timezone'] = event["setting"]
     elif event['type'] == "update_global_notifications":
         if event['notification_name'] == "enable_stream_desktop_notifications":
             state['enable_stream_desktop_notifications'] = event['setting']

zerver/tests/test_events.py

@@ -32,6 +32,7 @@
     do_change_is_admin,
     do_change_stream_description,
     do_change_subscription_property,
+    do_change_timezone,
     do_create_user,
     do_deactivate_stream,
     do_deactivate_user,
@@ -936,6 +937,19 @@ def test_change_default_language(self):
             error = schema_checker('events[0]', events[0])
             self.assert_on_error(error)
 
+    def test_change_timezone(self):
+        # type: () -> None
+        schema_checker = check_dict([
+            ('type', equals('update_display_settings')),
+            ('setting_name', equals('timezone')),
+            ('user', check_string),
+            ('setting', check_string),
+        ])
+        for setting_value in ['US/Mountain', 'US/Samoa', 'Pacific/Galapagos', '']:
+            events = self.do_test(lambda: do_change_timezone(self.user_profile, setting_value))
+            error = schema_checker('events[0]', events[0])
+            self.assert_on_error(error)
+
     def test_change_enable_stream_desktop_notifications(self):
         # type: () -> None
         schema_checker = check_dict([