[DeviceService] Move //device/time_zone_monitor to //services/device

services/device/public/interfaces/time_zone_monitor.mojom

 // Copyright 2016 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.
 
 module device.mojom;
 
 interface TimeZoneMonitor {
   // Add a client that will get notified on time zone changes. No throttling is
   // employed, as time zone changes are infrequent enough that there is no
   // realistic risk of flooding.
   AddClient(TimeZoneMonitorClient client);
 };
 
 interface TimeZoneMonitorClient {
   // Called on a time zone change. |tz_info| is the new time zone ID.
   OnTimeZoneChange(string tz_info);
 };