Revert "chromeos: Move files in //ash/common to //ash, part 1"

ash/system/system_clock_observer.cc

-// Copyright 2013 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 "ash/system/system_clock_observer.h"
-
-#include "ash/common/wm_shell.h"
-#include "ash/system/tray/system_tray_notifier.h"
-#include "chromeos/dbus/dbus_thread_manager.h"
-
-namespace ash {
-
-SystemClockObserver::SystemClockObserver() {
-  chromeos::DBusThreadManager::Get()->GetSystemClockClient()->AddObserver(this);
-  chromeos::system::TimezoneSettings::GetInstance()->AddObserver(this);
-  can_set_time_ =
-      chromeos::DBusThreadManager::Get()->GetSystemClockClient()->CanSetTime();
-}
-
-SystemClockObserver::~SystemClockObserver() {
-  chromeos::DBusThreadManager::Get()->GetSystemClockClient()->RemoveObserver(
-      this);
-  chromeos::system::TimezoneSettings::GetInstance()->RemoveObserver(this);
-}
-
-void SystemClockObserver::SystemClockUpdated() {
-  WmShell::Get()->system_tray_notifier()->NotifySystemClockTimeUpdated();
-}
-
-void SystemClockObserver::SystemClockCanSetTimeChanged(bool can_set_time) {
-  can_set_time_ = can_set_time;
-  WmShell::Get()->system_tray_notifier()->NotifySystemClockCanSetTimeChanged(
-      can_set_time_);
-}
-
-void SystemClockObserver::TimezoneChanged(const icu::TimeZone& timezone) {
-  WmShell::Get()->system_tray_notifier()->NotifyRefreshClock();
-}
-
-}  // namespace ash