Mojoify time zone update IPC from browser to renderer

device/time_zone_monitor/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);
+};