SystemMonitor refactoring: move power state monitor into a separate class called PowerMonitor

base/hi_res_timer_manager_unittest.cc

 // Copyright (c) 2012 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/hi_res_timer_manager.h"
 
 #include "base/memory/scoped_ptr.h"
-#include "base/system_monitor/system_monitor.h"
 #include "base/time.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_WIN)
 // http://crbug.com/114048
 TEST(HiResTimerManagerTest, DISABLED_ToggleOnOff) {
   MessageLoop loop;
-  scoped_ptr<base::SystemMonitor> system_monitor(new base::SystemMonitor());

[Hongbo Min, 2012/10/11 07:57:53]

No need to create PowerMonitor since the HighResolutionTimerManager ctor has
already accesses PowerMonitor via GetInstance.

[Hongbo Min, 2012/10/12 14:43:53]

Done.

   HighResolutionTimerManager manager;
 
   // At this point, we don't know if the high resolution timers are on or off,
   // it depends on what system the tests are running on (for example, if this
-  // test is running on a laptop/battery, then the SystemMonitor would have
+  // test is running on a laptop/battery, then the PowerMonitor would have
   // already set the PowerState to battery power; but if we're running on a
   // desktop, then the PowerState will be non-battery power).  Simulate a power
   // level change to get to a deterministic state.
   manager.OnPowerStateChange(/* on_battery */ false);
 
   // Loop a few times to test power toggling.
   for (int loop = 2; loop >= 0; --loop) {
     // The manager has the high resolution clock enabled now.
     EXPECT_TRUE(manager.hi_res_clock_available());
     // But the Time class has it off, because it hasn't been activated.
@@ skipping 11 matching lines @@
     // Simulate a off-battery power event.
     manager.OnPowerStateChange(/* on_battery */ false);
     EXPECT_TRUE(manager.hi_res_clock_available());
     EXPECT_TRUE(base::Time::IsHighResolutionTimerInUse());
 
     // De-activate the high resolution timer.
     base::Time::ActivateHighResolutionTimer(false);
   }
 }
 #endif  // defined(OS_WIN)