Move SystemMonitor to src/chrome/common....

app/hi_res_timer_manager_win.cc

-// Copyright (c) 2009 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 "app/hi_res_timer_manager.h"
-
-#include "base/time.h"
-
-HighResolutionTimerManager::HighResolutionTimerManager()
-    : hi_res_clock_used_(false) {
-  SystemMonitor* system_monitor = SystemMonitor::Get();
-  system_monitor->AddObserver(this);
-  UseHiResClock(!system_monitor->BatteryPower());
-}
-
-HighResolutionTimerManager::~HighResolutionTimerManager() {
-  SystemMonitor::Get()->RemoveObserver(this);
-  UseHiResClock(false);
-}
-
-void HighResolutionTimerManager::OnPowerStateChange(bool on_battery_power) {
-  UseHiResClock(!on_battery_power);
-}
-
-void HighResolutionTimerManager::UseHiResClock(bool use) {
-  if (use == hi_res_clock_used_)
-    return;
-  base::Time::EnableHighResolutionTimer(use);
-}