Simple cleanup.

base/system_monitor.cc

 // Copyright (c) 2008 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 "base/system_monitor.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
+#include "base/singleton.h"
 
 namespace base {
 
 #if defined(ENABLE_BATTERY_MONITORING)
 // The amount of time (in ms) to wait before running the initial
 // battery check.
 static int kDelayedBatteryCheckMs = 10 * 1000;
 #endif  // defined(ENABLE_BATTERY_MONITORING)
 
 SystemMonitor::SystemMonitor()
@@ skipping 47 matching lines @@
 void SystemMonitor::NotifySuspend() {
   LOG(INFO) << L"Power Suspending";
   observer_list_->Notify(&PowerObserver::OnSuspend, this);
 }
 
 void SystemMonitor::NotifyResume() {
   LOG(INFO) << L"Power Resuming";
   observer_list_->Notify(&PowerObserver::OnResume, this);
 }
 
+// static
+SystemMonitor* SystemMonitor::Get() {
+  // Uses the LeakySingletonTrait because cleanup is optional.
+  return
+      Singleton<SystemMonitor, LeakySingletonTraits<SystemMonitor> >::get();
+}
+
+// static
 void SystemMonitor::Start() {
 #if defined(ENABLE_BATTERY_MONITORING)
   DCHECK(MessageLoop::current());  // Can't call start too early.
   SystemMonitor* monitor = Get();
   monitor->delayed_battery_check_.Start(
       TimeDelta::FromMilliseconds(kDelayedBatteryCheckMs), monitor,
       &SystemMonitor::BatteryCheck);
 #endif  // defined(ENABLE_BATTERY_MONITORING)
 }
 
 void SystemMonitor::BatteryCheck() {
   ProcessPowerMessage(SystemMonitor::POWER_STATE_EVENT);
 }
 
 } // namespace base