Make SystemMonitor not a Singleton and move it out of base

SystemMonitor makes an assumption that through its lifetime a MessageLoop exists and stays the same. It is difficult and error-prone to satisfy that when it is a Singleton. It has caused problems in the past.

Additionally, extract HighResoltionTimerManager out of time_win.cc, eliminating yet another Singleton.

TEST=none
BUG=none

Review URL: http://codereview.chromium.org/431008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@33214 0039d316-1c4b-4281-b951-d872f2087c98

27 files changed, 195 insertions, 184 deletions

diff --git a/app/app.gyp b/app/app.gyp
index 78f9978..4ddfb8a 100644
--- a/app/app.gyp
+++ b/app/app.gyp
@@ -105,6 +105,9 @@
         'gfx/text_elider.h',
         'gtk_dnd_util.cc',
         'gtk_dnd_util.h',
+        'hi_res_timer_manager_posix.cc',
+        'hi_res_timer_manager_win.cc',
+        'hi_res_timer_manager.h',
         'l10n_util.cc',
         'l10n_util.h',
         'l10n_util_mac.h',
@@ -134,6 +137,10 @@
         'sql/statement.h',
         'sql/transaction.cc',
         'sql/transaction.h',
+        'system_monitor.cc',
+        'system_monitor.h',
+        'system_monitor_posix.cc',
+        'system_monitor_win.cc',
         'table_model.cc',
         'table_model.h',
         'table_model_observer.h',
@@ -244,6 +251,7 @@
         'l10n_util_unittest.cc',
         'os_exchange_data_win_unittest.cc',
         'run_all_unittests.cc',
+        'system_monitor_unittest.cc',
         'test_suite.h',
         'sql/connection_unittest.cc',
         'sql/statement_unittest.cc',
diff --git a/app/hi_res_timer_manager.h b/app/hi_res_timer_manager.h
new file mode 100644
index 0000000..17a0522
--- /dev/null
+++ b/app/hi_res_timer_manager.h
@@ -0,0 +1,29 @@
+// 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.
+
+#ifndef APP_HI_RES_TIMER_MANAGER_H_
+#define APP_HI_RES_TIMER_MANAGER_H_
+
+#include "app/system_monitor.h"
+
+// Ensures that the Windows high resolution timer is only used
+// when not running on battery power.
+class HighResolutionTimerManager : public SystemMonitor::PowerObserver {
+ public:
+  HighResolutionTimerManager();
+  virtual ~HighResolutionTimerManager();
+
+  // SystemMonitor::PowerObserver:
+  void OnPowerStateChange(bool on_battery_power);
+
+ private:
+  // Enable or disable the faster multimedia timer.
+  void UseHiResClock(bool use);
+
+  bool hi_res_clock_used_;
+
+  DISALLOW_COPY_AND_ASSIGN(HighResolutionTimerManager);
+};
+
+#endif  // APP_HI_RES_TIMER_MANAGER_H_
diff --git a/app/hi_res_timer_manager_posix.cc b/app/hi_res_timer_manager_posix.cc
new file mode 100644
index 0000000..f0562fd
--- /dev/null
+++ b/app/hi_res_timer_manager_posix.cc
@@ -0,0 +1,19 @@
+// 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"
+
+// On POSIX we don't need to do anything special with the system timer.
+
+HighResolutionTimerManager::HighResolutionTimerManager() {
+}
+
+HighResolutionTimerManager::~HighResolutionTimerManager() {
+}
+
+void HighResolutionTimerManager::OnPowerStateChange(bool on_battery_power) {
+}
+
+void HighResolutionTimerManager::UseHiResClock(bool use) {
+}
diff --git a/app/hi_res_timer_manager_win.cc b/app/hi_res_timer_manager_win.cc
new file mode 100644
index 0000000..b7cee1d
--- /dev/null
+++ b/app/hi_res_timer_manager_win.cc
@@ -0,0 +1,31 @@
+// 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;
+  bool result = base::Time::UseHighResolutionTimer(use);
+  DCHECK(result);
+  hi_res_clock_used_ = use;
+}
diff --git a/base/system_monitor.cc b/app/system_monitor.cc
index 44cdce5..b0e715a 100644
--- a/base/system_monitor.cc
+++ b/app/system_monitor.cc
@@ -1,13 +1,14 @@
-// Copyright (c) 2008 The Chromium Authors. All rights reserved.
+// 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 "base/system_monitor.h"
+#include "app/system_monitor.h"
+
 #include "base/logging.h"
 #include "base/message_loop.h"
-#include "base/singleton.h"
+#include "base/time.h"
 
-namespace base {
+static SystemMonitor* g_system_monitor = NULL;
 
 #if defined(ENABLE_BATTERY_MONITORING)
 // The amount of time (in ms) to wait before running the initial
@@ -16,9 +17,28 @@ static int kDelayedBatteryCheckMs = 10 * 1000;
 #endif  // defined(ENABLE_BATTERY_MONITORING)
 
 SystemMonitor::SystemMonitor()
-    : battery_in_use_(false),
+    : observer_list_(new ObserverListThreadSafe<PowerObserver>()),
+      battery_in_use_(false),
       suspended_(false) {
-  observer_list_ = new ObserverListThreadSafe<PowerObserver>();
+  DCHECK(!g_system_monitor);
+  g_system_monitor = this;
+
+  DCHECK(MessageLoop::current());
+#if defined(ENABLE_BATTERY_MONITORING)
+  delayed_battery_check_.Start(
+      base::TimeDelta::FromMilliseconds(kDelayedBatteryCheckMs), this,
+      &SystemMonitor::BatteryCheck);
+#endif  // defined(ENABLE_BATTERY_MONITORING)
+}
+
+SystemMonitor::~SystemMonitor() {
+  DCHECK_EQ(this, g_system_monitor);
+  g_system_monitor = NULL;
+}
+
+// static
+SystemMonitor* SystemMonitor::Get() {
+  return g_system_monitor;
 }
 
 void SystemMonitor::ProcessPowerMessage(PowerEvent event_id) {
@@ -73,26 +93,6 @@ void SystemMonitor::NotifyResume() {
   observer_list_->Notify(&PowerObserver::OnResume);
 }
 
-// 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
diff --git a/base/system_monitor.h b/app/system_monitor.h
index 71d8436..abafe4f 100644
--- a/base/system_monitor.h
+++ b/app/system_monitor.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef BASE_SYSTEM_MONITOR_H_
-#define BASE_SYSTEM_MONITOR_H_
+#ifndef APP_SYSTEM_MONITOR_H_
+#define APP_SYSTEM_MONITOR_H_
 
 #include "build/build_config.h"
 
@@ -20,23 +20,18 @@
 #include "base/timer.h"
 #endif  // defined(ENABLE_BATTERY_MONITORING)
 
-namespace base {
-
 // Class for monitoring various system-related subsystems
 // such as power management, network status, etc.
 // TODO(mbelshe):  Add support beyond just power management.
 class SystemMonitor {
  public:
-  // Retrieves the Singleton.
-  static SystemMonitor* Get();
+  // Create SystemMonitor. Only one SystemMonitor instance per application
+  // is allowed.
+  SystemMonitor();
+  ~SystemMonitor();
 
-  // Start the System Monitor within a process.  This method
-  // is provided so that the battery check can be deferred.
-  // The MessageLoop must be started before calling this
-  // method.
-  // This is a no-op on platforms for which ENABLE_BATTERY_MONITORING is
-  // disabled.
-  static void Start();
+  // Get the application-wide SystemMonitor (if not present, returns NULL).
+  static SystemMonitor* Get();
 
   //
   // Power-related APIs
@@ -94,10 +89,6 @@ class SystemMonitor {
   // Cross-platform handling of a power event.
   void ProcessPowerMessage(PowerEvent event_id);
 
-  // Constructor.
-  // Don't use this; access SystemMonitor via the Singleton.
-  SystemMonitor();
-
  private:
   // Platform-specific method to check whether the system is currently
   // running on battery power.  Returns true if running on batteries,
@@ -124,6 +115,4 @@ class SystemMonitor {
   DISALLOW_COPY_AND_ASSIGN(SystemMonitor);
 };
 
-}
-
-#endif  // BASE_SYSTEM_MONITOR_H_
+#endif  // APP_SYSTEM_MONITOR_H_
diff --git a/base/system_monitor_posix.cc b/app/system_monitor_posix.cc
index a4a118c..5ac7a12 100644
--- a/base/system_monitor_posix.cc
+++ b/app/system_monitor_posix.cc
@@ -1,14 +1,10 @@
-// Copyright (c) 2008 The Chromium Authors. All rights reserved.
+// 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 "base/system_monitor.h"
-
-namespace base {
+#include "app/system_monitor.h"
 
 bool SystemMonitor::IsBatteryPower() {
   NOTIMPLEMENTED();
   return false;
 }
-
-} // namespace base
diff --git a/base/system_monitor_unittest.cc b/app/system_monitor_unittest.cc
index 7ba3a6b..5b107aa 100644
--- a/base/system_monitor_unittest.cc
+++ b/app/system_monitor_unittest.cc
@@ -2,16 +2,17 @@
 // 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 "app/system_monitor.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
-class PowerTest : public base::SystemMonitor::PowerObserver {
+class PowerTest : public SystemMonitor::PowerObserver {
  public:
   PowerTest()
       : battery_(false),
         power_state_changes_(0),
         suspends_(0),
-        resumes_(0) {};
+        resumes_(0) {
+  }
 
   // PowerObserver callbacks.
   void OnPowerStateChange(bool on_battery_power) {
@@ -47,40 +48,40 @@ TEST(SystemMonitor, PowerNotifications) {
   // Initialize time() since it registers as a SystemMonitor observer.
   base::Time now = base::Time::Now();
 
-  base::SystemMonitor* system_monitor = base::SystemMonitor::Get();
+  SystemMonitor system_monitor;
   PowerTest test[kObservers];
   for (int index = 0; index < kObservers; ++index)
-    system_monitor->AddObserver(&test[index]);
+    system_monitor.AddObserver(&test[index]);
 
   // Send a bunch of power changes.  Since the battery power hasn't
   // actually changed, we shouldn't get notifications.
   for (int index = 0; index < 5; index++) {
-    system_monitor->ProcessPowerMessage(base::SystemMonitor::POWER_STATE_EVENT);
+    system_monitor.ProcessPowerMessage(SystemMonitor::POWER_STATE_EVENT);
     EXPECT_EQ(test[0].power_state_changes(), 0);
   }
 
   // Sending resume when not suspended should have no effect.
-  system_monitor->ProcessPowerMessage(base::SystemMonitor::RESUME_EVENT);
+  system_monitor.ProcessPowerMessage(SystemMonitor::RESUME_EVENT);
   loop.RunAllPending();
   EXPECT_EQ(test[0].resumes(), 0);
 
   // Pretend we suspended.
-  system_monitor->ProcessPowerMessage(base::SystemMonitor::SUSPEND_EVENT);
+  system_monitor.ProcessPowerMessage(SystemMonitor::SUSPEND_EVENT);
   loop.RunAllPending();
   EXPECT_EQ(test[0].suspends(), 1);
 
   // Send a second suspend notification.  This should be suppressed.
-  system_monitor->ProcessPowerMessage(base::SystemMonitor::SUSPEND_EVENT);
+  system_monitor.ProcessPowerMessage(SystemMonitor::SUSPEND_EVENT);
   loop.RunAllPending();
   EXPECT_EQ(test[0].suspends(), 1);
 
   // Pretend we were awakened.
-  system_monitor->ProcessPowerMessage(base::SystemMonitor::RESUME_EVENT);
+  system_monitor.ProcessPowerMessage(SystemMonitor::RESUME_EVENT);
   loop.RunAllPending();
   EXPECT_EQ(test[0].resumes(), 1);
 
   // Send a duplicate resume notification.  This should be suppressed.
-  system_monitor->ProcessPowerMessage(base::SystemMonitor::RESUME_EVENT);
+  system_monitor.ProcessPowerMessage(SystemMonitor::RESUME_EVENT);
   loop.RunAllPending();
   EXPECT_EQ(test[0].resumes(), 1);
 }
diff --git a/base/system_monitor_win.cc b/app/system_monitor_win.cc
index 8a2d8c9..c9347dc 100644
--- a/base/system_monitor_win.cc
+++ b/app/system_monitor_win.cc
@@ -1,10 +1,8 @@
-// Copyright (c) 2008 The Chromium Authors. All rights reserved.
+// 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 "base/system_monitor.h"
-
-namespace base {
+#include "app/system_monitor.h"
 
 void SystemMonitor::ProcessWmPowerBroadcastMessage(int event_id) {
   PowerEvent power_event;
@@ -46,7 +44,3 @@ bool SystemMonitor::IsBatteryPower() {
   }
   return (status.ACLineStatus == 0);
 }
-
-
-
-} // namespace base
diff --git a/base/base.gyp b/base/base.gyp
index 7238928..23b85b1 100644
--- a/base/base.gyp
+++ b/base/base.gyp
@@ -321,10 +321,6 @@
         'sys_string_conversions_linux.cc',
         'sys_string_conversions_mac.mm',
         'sys_string_conversions_win.cc',
-        'system_monitor.cc',
-        'system_monitor.h',
-        'system_monitor_posix.cc',
-        'system_monitor_win.cc',
         'task.h',
         'thread.cc',
         'thread.h',
@@ -654,7 +650,6 @@
         'sys_info_unittest.cc',
         'sys_string_conversions_mac_unittest.mm',
         'sys_string_conversions_unittest.cc',
-        'system_monitor_unittest.cc',
         'task_unittest.cc',
         'thread_collision_warner_unittest.cc',
         'thread_local_storage_unittest.cc',
diff --git a/base/test/test_suite.h b/base/test/test_suite.h
index 44e8511..2566b1a 100644
--- a/base/test/test_suite.h
+++ b/base/test/test_suite.h
@@ -182,10 +182,10 @@ class TestSuite {
 
     CHECK(base::EnableInProcessStackDumping());
 #if defined(OS_WIN)
-    // For unit tests we turn on the high resolution timer and disable
-    // base::Time's use of SystemMonitor. Tests create and destroy the message
-    // loop, which causes a crash with SystemMonitor (http://crbug.com/12187).
-    base::Time::EnableHiResClockForTests();
+    // Make sure we run with high resolution timer to minimize differences
+    // between production code and test code.
+    bool result = base::Time::UseHighResolutionTimer(true);
+    CHECK(result);
 
     // In some cases, we do not want to see standard error dialogs.
     if (!IsDebuggerPresent() &&
diff --git a/base/time.h b/base/time.h
index 8cd752a..33ab227 100644
--- a/base/time.h
+++ b/base/time.h
@@ -242,12 +242,9 @@ class Time {
   static Time FromFileTime(FILETIME ft);
   FILETIME ToFileTime() const;
 
-  // Monitor system power state and disable high resolution timer when we're
-  // on battery. See time_win.cc for more details.
-  static void StartSystemMonitorObserver();
-
-  // Enable high resolution timer unconditionally. Only for test code.
-  static void EnableHiResClockForTests();
+  // Enable or disable Windows high resolution timer. For more details
+  // see comments in time_win.cc. Returns true on success.
+  static bool UseHighResolutionTimer(bool use);
 #endif
 
   // Converts an exploded structure representing either the local time or UTC
diff --git a/base/time_win.cc b/base/time_win.cc
index 9fdcab1..eedf468 100644
--- a/base/time_win.cc
+++ b/base/time_win.cc
@@ -45,7 +45,6 @@
 #include "base/logging.h"
 #include "base/cpu.h"
 #include "base/singleton.h"
-#include "base/system_monitor.h"
 
 using base::Time;
 using base::TimeDelta;
@@ -88,65 +87,6 @@ void InitializeClock() {
   initial_time = CurrentWallclockMicroseconds();
 }
 
-class HighResolutionTimerManager : public base::SystemMonitor::PowerObserver {
- public:
-  ~HighResolutionTimerManager() {
-    StopMonitoring();
-    UseHiResClock(false);
-  }
-
-  void Enable() {
-    StopMonitoring();
-    UseHiResClock(true);
-  }
-
-  void StartMonitoring() {
-    if (is_monitoring_)
-      return;
-    is_monitoring_ = true;
-    base::SystemMonitor* system_monitor = base::SystemMonitor::Get();
-    system_monitor->AddObserver(this);
-    UseHiResClock(!system_monitor->BatteryPower());
-  }
-
-  void StopMonitoring() {
-    if (!is_monitoring_)
-      return;
-    is_monitoring_ = false;
-    base::SystemMonitor* system_monitor = base::SystemMonitor::Get();
-    if (system_monitor)
-      system_monitor->RemoveObserver(this);
-  }
-
-  // Interfaces for monitoring Power changes.
-  void OnPowerStateChange(bool on_battery_power) {
-    UseHiResClock(!on_battery_power);
-  }
-
- private:
-  HighResolutionTimerManager()
-      : is_monitoring_(false),
-        hi_res_clock_enabled_(false) {
-  }
-  friend struct DefaultSingletonTraits<HighResolutionTimerManager>;
-
-  // Enable or disable the faster multimedia timer.
-  void UseHiResClock(bool enabled) {
-    if (enabled == hi_res_clock_enabled_)
-      return;
-    if (enabled)
-      timeBeginPeriod(1);
-    else
-      timeEndPeriod(1);
-    hi_res_clock_enabled_ = enabled;
-  }
-
-  bool is_monitoring_;
-  bool hi_res_clock_enabled_;
-
-  DISALLOW_COPY_AND_ASSIGN(HighResolutionTimerManager);
-};
-
 }  // namespace
 
 // Time -----------------------------------------------------------------------
@@ -208,13 +148,18 @@ FILETIME Time::ToFileTime() const {
 }
 
 // static
-void Time::StartSystemMonitorObserver() {
-  Singleton<HighResolutionTimerManager>()->StartMonitoring();
-}
-
-// static
-void Time::EnableHiResClockForTests() {
-  Singleton<HighResolutionTimerManager>()->Enable();
+bool Time::UseHighResolutionTimer(bool use) {
+  // TODO(mbelshe): Make sure that switching the system timer resolution
+  // doesn't break Timer firing order etc. An example test would be to have
+  // two threads. One would have a bunch of timers, and another would turn the
+  // high resolution timer on and off.
+
+  MMRESULT result;
+  if (use)
+    result = timeBeginPeriod(1);
+  else
+    result = timeEndPeriod(1);
+  return (result == TIMERR_NOERROR);
 }
 
 // static
diff --git a/chrome/browser/browser_main.cc b/chrome/browser/browser_main.cc
index a452dab..28ba351 100644
--- a/chrome/browser/browser_main.cc
+++ b/chrome/browser/browser_main.cc
@@ -6,8 +6,10 @@
 
 #include <algorithm>
 
+#include "app/hi_res_timer_manager.h"
 #include "app/l10n_util.h"
 #include "app/resource_bundle.h"
+#include "app/system_monitor.h"
 #include "base/command_line.h"
 #include "base/field_trial.h"
 #include "base/file_util.h"
@@ -19,7 +21,6 @@
 #include "base/string_piece.h"
 #include "base/string_util.h"
 #include "base/sys_string_conversions.h"
-#include "base/system_monitor.h"
 #include "base/time.h"
 #include "base/tracked_objects.h"
 #include "base/values.h"
@@ -340,13 +341,8 @@ int BrowserMain(const MainFunctionParams& parameters) {
 
   MessageLoop main_message_loop(MessageLoop::TYPE_UI);
 
-  // Initialize the SystemMonitor
-  base::SystemMonitor::Start();
-#if defined(OS_WIN)
-  // We want to monitor system power state to adjust our high resolution
-  // timer settings. But it's necessary only on Windows.
-  base::Time::StartSystemMonitorObserver();
-#endif  // defined(OS_WIN)
+  SystemMonitor system_monitor;
+  HighResolutionTimerManager hi_res_timer_manager;
 
   // Initialize statistical testing infrastructure.
   FieldTrialList field_trial;
diff --git a/chrome/browser/profile_manager.cc b/chrome/browser/profile_manager.cc
index 2a20bdc..9b66e39 100644
--- a/chrome/browser/profile_manager.cc
+++ b/chrome/browser/profile_manager.cc
@@ -42,11 +42,11 @@ void ProfileManager::ShutdownSessionServices() {
 }
 
 ProfileManager::ProfileManager() {
-  base::SystemMonitor::Get()->AddObserver(this);
+  SystemMonitor::Get()->AddObserver(this);
 }
 
 ProfileManager::~ProfileManager() {
-  base::SystemMonitor* system_monitor = base::SystemMonitor::Get();
+  SystemMonitor* system_monitor = SystemMonitor::Get();
   if (system_monitor)
     system_monitor->RemoveObserver(this);
 
diff --git a/chrome/browser/profile_manager.h b/chrome/browser/profile_manager.h
index ecbbfc8..b52c7db 100644
--- a/chrome/browser/profile_manager.h
+++ b/chrome/browser/profile_manager.h
@@ -11,11 +11,11 @@
 #include <string>
 #include <vector>
 
+#include "app/system_monitor.h"
 #include "base/basictypes.h"
 #include "base/file_path.h"
 #include "base/message_loop.h"
 #include "base/non_thread_safe.h"
-#include "base/system_monitor.h"
 #include "base/values.h"
 #include "chrome/browser/profile.h"
 
@@ -63,7 +63,7 @@ class AvailableProfile {
 };
 
 class ProfileManager : public NonThreadSafe,
-                       public base::SystemMonitor::PowerObserver {
+                       public SystemMonitor::PowerObserver {
  public:
   ProfileManager();
   virtual ~ProfileManager();
diff --git a/chrome/browser/tabs/tab_strip_model_unittest.cc b/chrome/browser/tabs/tab_strip_model_unittest.cc
index 70331f9..00afd03 100644
--- a/chrome/browser/tabs/tab_strip_model_unittest.cc
+++ b/chrome/browser/tabs/tab_strip_model_unittest.cc
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "app/system_monitor.h"
 #include "base/file_util.h"
 #include "base/path_service.h"
 #include "base/string_util.h"
@@ -151,6 +152,10 @@ class TabStripModelTest : public RenderViewHostTestHarness {
   std::wstring test_dir_;
   std::wstring profile_path_;
   std::map<TabContents*, int> foo_;
+
+  // ProfileManager requires a SystemMonitor.
+  SystemMonitor system_monitor;
+
   ProfileManager pm_;
 };
 
diff --git a/chrome/chrome.gyp b/chrome/chrome.gyp
index c921070..c73946e 100755
--- a/chrome/chrome.gyp
+++ b/chrome/chrome.gyp
@@ -739,6 +739,8 @@
           ],
         }, { # else: OS != "win"
           'sources!': [
+            'common/hi_res_timer_manager.cc',
+            'common/hi_res_timer_manager.h',
             'common/temp_scaffolding_stubs.h',
           ],
         }],
diff --git a/chrome/nacl/nacl_main.cc b/chrome/nacl/nacl_main.cc
index 0516495..5271cf4 100644
--- a/chrome/nacl/nacl_main.cc
+++ b/chrome/nacl/nacl_main.cc
@@ -10,10 +10,11 @@
 #include "sandbox/src/sandbox.h"
 #endif
 
+#include "app/hi_res_timer_manager.h"
+#include "app/system_monitor.h"
 #include "base/command_line.h"
 #include "base/message_loop.h"
 #include "base/string_util.h"
-#include "base/system_monitor.h"
 #include "chrome/common/child_process.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_switches.h"
@@ -28,8 +29,8 @@ int NaClMain(const MainFunctionParams& parameters) {
   std::wstring app_name = chrome::kBrowserAppName;
   PlatformThread::SetName(WideToASCII(app_name + L"_NaClMain").c_str());
 
-  // Initialize the SystemMonitor
-  base::SystemMonitor::Start();
+  SystemMonitor system_monitor;
+  HighResolutionTimerManager hi_res_timer_manager;
 
 #if defined(OS_WIN)
   const CommandLine& parsed_command_line = parameters.command_line_;
diff --git a/chrome/plugin/plugin_main.cc b/chrome/plugin/plugin_main.cc
index 0b67360..9794305 100644
--- a/chrome/plugin/plugin_main.cc
+++ b/chrome/plugin/plugin_main.cc
@@ -4,13 +4,14 @@
 
 #include "build/build_config.h"
 
+#include "app/hi_res_timer_manager.h"
+#include "app/system_monitor.h"
 #if defined(OS_WIN)
 #include "app/win_util.h"
 #endif
 #include "base/command_line.h"
 #include "base/message_loop.h"
 #include "base/string_util.h"
-#include "base/system_monitor.h"
 #include "chrome/common/child_process.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_switches.h"
@@ -89,8 +90,8 @@ int PluginMain(const MainFunctionParams& parameters) {
   std::wstring app_name = chrome::kBrowserAppName;
   PlatformThread::SetName(WideToASCII(app_name + L"_PluginMain").c_str());
 
-  // Initialize the SystemMonitor
-  base::SystemMonitor::Start();
+  SystemMonitor system_monitor;
+  HighResolutionTimerManager high_resolution_timer_manager;
 
 #if defined(OS_MACOSX)
   TrimInterposeEnvironment();
diff --git a/chrome/profile_import/profile_import_main.cc b/chrome/profile_import/profile_import_main.cc
index 11b1aed..546df18 100644
--- a/chrome/profile_import/profile_import_main.cc
+++ b/chrome/profile_import/profile_import_main.cc
@@ -5,7 +5,6 @@
 #include "base/command_line.h"
 #include "base/message_loop.h"
 #include "base/string_util.h"
-#include "base/system_monitor.h"
 #include "chrome/common/child_process.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_switches.h"
diff --git a/chrome/renderer/renderer_main.cc b/chrome/renderer/renderer_main.cc
index 1531c40..c8f89c9 100644
--- a/chrome/renderer/renderer_main.cc
+++ b/chrome/renderer/renderer_main.cc
@@ -2,8 +2,10 @@
 // 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 "app/l10n_util.h"
 #include "app/resource_bundle.h"
+#include "app/system_monitor.h"
 #include "base/command_line.h"
 #include "base/field_trial.h"
 #include "base/histogram.h"
@@ -14,7 +16,6 @@
 #include "base/scoped_nsautorelease_pool.h"
 #include "base/stats_counters.h"
 #include "base/string_util.h"
-#include "base/system_monitor.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_counters.h"
 #include "chrome/common/chrome_switches.h"
@@ -88,8 +89,8 @@ int RendererMain(const MainFunctionParams& parameters) {
   std::wstring app_name = chrome::kBrowserAppName;
   PlatformThread::SetName(WideToASCII(app_name + L"_RendererMain").c_str());
 
-  // Initialize the SystemMonitor
-  base::SystemMonitor::Start();
+  SystemMonitor system_monitor;
+  HighResolutionTimerManager hi_res_timer_manager;
 
   platform.PlatformInitialize();
 
diff --git a/chrome/utility/utility_main.cc b/chrome/utility/utility_main.cc
index b2eaa46..690d47b1 100644
--- a/chrome/utility/utility_main.cc
+++ b/chrome/utility/utility_main.cc
@@ -3,10 +3,11 @@
 // found in the LICENSE file.
 
 #include "app/app_switches.h"
+#include "app/hi_res_timer_manager.h"
+#include "app/system_monitor.h"
 #include "base/command_line.h"
 #include "base/message_loop.h"
 #include "base/string_util.h"
-#include "base/system_monitor.h"
 #include "chrome/common/child_process.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_switches.h"
@@ -27,8 +28,8 @@ int UtilityMain(const MainFunctionParams& parameters) {
   std::wstring app_name = chrome::kBrowserAppName;
   PlatformThread::SetName(WideToASCII(app_name + L"_UtilityMain").c_str());
 
-  // Initialize the SystemMonitor
-  base::SystemMonitor::Start();
+  SystemMonitor system_monitor;
+  HighResolutionTimerManager hi_res_timer_manager;
 
   ChildProcess utility_process;
   utility_process.set_main_thread(new UtilityThread());
diff --git a/chrome/worker/worker_main.cc b/chrome/worker/worker_main.cc
index b157dbe..a91ac74 100644
--- a/chrome/worker/worker_main.cc
+++ b/chrome/worker/worker_main.cc
@@ -2,10 +2,11 @@
 // 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 "app/system_monitor.h"
 #include "base/command_line.h"
 #include "base/message_loop.h"
 #include "base/string_util.h"
-#include "base/system_monitor.h"
 #include "chrome/common/child_process.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_switches.h"
@@ -25,8 +26,8 @@ int WorkerMain(const MainFunctionParams& parameters) {
   std::wstring app_name = chrome::kBrowserAppName;
   PlatformThread::SetName(WideToASCII(app_name + L"_WorkerMain").c_str());
 
-  // Initialize the SystemMonitor
-  base::SystemMonitor::Start();
+  SystemMonitor system_monitor;
+  HighResolutionTimerManager hi_res_timer_manager;
 
   ChildProcess worker_process;
   worker_process.set_main_thread(new WorkerThread());
diff --git a/chrome_frame/test/net/fake_external_tab.cc b/chrome_frame/test/net/fake_external_tab.cc
index cc31331..2ea35d9 100644
--- a/chrome_frame/test/net/fake_external_tab.cc
+++ b/chrome_frame/test/net/fake_external_tab.cc
@@ -255,7 +255,7 @@ void CFUrlRequestUnittestRunner::Initialize() {
   // directly because it will attempt to initialize some things such as
   // ICU that have already been initialized for this process.
   InitializeLogging();
-  base::Time::EnableHiResClockForTests();
+  base::Time::UseHighResolutionTimer(true);
 
 #if !defined(PURIFY) && defined(OS_WIN)
   logging::SetLogAssertHandler(UnitTestAssertHandler);
diff --git a/views/widget/widget_win.cc b/views/widget/widget_win.cc
index 79956a8..892d47f 100644
--- a/views/widget/widget_win.cc
+++ b/views/widget/widget_win.cc
@@ -8,6 +8,7 @@
 #include "app/gfx/native_theme_win.h"
 #include "app/gfx/path.h"
 #include "app/l10n_util_win.h"
+#include "app/system_monitor.h"
 #include "app/win_util.h"
 #include "base/string_util.h"
 #include "base/win_util.h"
@@ -770,7 +771,7 @@ void WidgetWin::OnPaint(HDC dc) {
 }
 
 LRESULT WidgetWin::OnPowerBroadcast(DWORD power_event, DWORD data) {
-  base::SystemMonitor* monitor = base::SystemMonitor::Get();
+  SystemMonitor* monitor = SystemMonitor::Get();
   if (monitor)
     monitor->ProcessWmPowerBroadcastMessage(power_event);
   SetMsgHandled(FALSE);
diff --git a/views/widget/widget_win.h b/views/widget/widget_win.h
index 3f06ca3..43c4357 100644
--- a/views/widget/widget_win.h
+++ b/views/widget/widget_win.h
@@ -13,7 +13,6 @@
 #include "app/win/window_impl.h"
 #include "base/message_loop.h"
 #include "base/scoped_comptr_win.h"
-#include "base/system_monitor.h"
 #include "views/focus/focus_manager.h"
 #include "views/layout_manager.h"
 #include "views/widget/widget.h"