mash: Add SystemTrayClient interface, use to show date settings

chrome/browser/ui/ash/system_tray_controller_mus.cc

-// 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.
-
-#include "chrome/browser/ui/ash/system_tray_controller_mus.h"
-
-#include "chrome/browser/browser_process.h"
-#include "chrome/browser/browser_process_platform_part.h"
-#include "chrome/browser/chromeos/system/system_clock.h"
-#include "content/public/common/mojo_shell_connection.h"
-#include "services/shell/public/cpp/connector.h"
-
-SystemTrayControllerMus::SystemTrayControllerMus() {
-  shell::Connector* connector =
-      content::MojoShellConnection::GetForProcess()->GetConnector();
-  connector->ConnectToInterface("mojo:ash", &system_tray_);
-
-  g_browser_process->platform_part()->GetSystemClock()->AddObserver(this);
-}
-
-SystemTrayControllerMus::~SystemTrayControllerMus() {
-  g_browser_process->platform_part()->GetSystemClock()->RemoveObserver(this);
-}
-
-void SystemTrayControllerMus::OnSystemClockChanged(
-    chromeos::system::SystemClock* clock) {
-  system_tray_->SetUse24HourClock(clock->ShouldUse24HourClock());
-}