Make UserActivityDetector a singleton

chrome/browser/chromeos/app_mode/kiosk_mode_idle_app_name_notification.cc

 // Copyright 2014 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 "chrome/browser/chromeos/app_mode/kiosk_mode_idle_app_name_notification.h"
 
-#include "ash/shell.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "chrome/browser/chromeos/ui/idle_app_name_notification_view.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/common/chrome_switches.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "components/user_manager/user_manager.h"
 #include "extensions/browser/extension_system.h"
@@ skipping 32 matching lines @@
 }
 
 KioskModeIdleAppNameNotification::KioskModeIdleAppNameNotification()
     : show_notification_upon_next_user_activity_(false) {
   // Note: The timeout is currently fixed. If that changes we need to check if
   // the KioskModeSettings were already initialized.
   Setup();
 }
 
 KioskModeIdleAppNameNotification::~KioskModeIdleAppNameNotification() {
-  if (ash::Shell::HasInstance() &&
-      ash::Shell::GetInstance()->user_activity_detector()->HasObserver(this)) {
-    ash::Shell::GetInstance()->user_activity_detector()->RemoveObserver(this);
+  wm::UserActivityDetector* user_activity_detector =
+      wm::UserActivityDetector::Get();
+  if (user_activity_detector && user_activity_detector->HasObserver(this)) {
+    user_activity_detector->RemoveObserver(this);
     // At this time the DBusThreadManager might already be gone.
     if (chromeos::DBusThreadManager::IsInitialized())
       chromeos::DBusThreadManager::Get()->GetPowerManagerClient(
           )->RemoveObserver(this);
   }
 }
 
 void KioskModeIdleAppNameNotification::Setup() {
   DCHECK(user_manager::UserManager::Get()->IsUserLoggedIn());
   Start();
@@ skipping 18 matching lines @@
 
 void KioskModeIdleAppNameNotification::SuspendDone(
     const base::TimeDelta& sleep_duration) {
   // When we come back from a system resume we stop the timer and show the
   // message.
   timer_.Stop();
   OnTimeout();
 }
 
 void KioskModeIdleAppNameNotification::Start() {
-  if (!ash::Shell::GetInstance()->user_activity_detector()->HasObserver(this)) {
-    ash::Shell::GetInstance()->user_activity_detector()->AddObserver(this);
+  if (!wm::UserActivityDetector::Get()->HasObserver(this)) {
+    wm::UserActivityDetector::Get()->AddObserver(this);
     chromeos::DBusThreadManager::Get()->GetPowerManagerClient()->AddObserver(
         this);
   }
   ResetTimer();
 }
 
 void KioskModeIdleAppNameNotification::ResetTimer() {
   if (timer_.IsRunning()) {
     timer_.Reset();
   } else {
     // OneShotTimer destroys the posted task after running it, so Reset()
     // isn't safe to call on a timer that's already fired.
     timer_.Start(
         FROM_HERE,
         base::TimeDelta::FromMilliseconds(kIdleAppNameNotificationTimeoutMs),
         base::Bind(&KioskModeIdleAppNameNotification::OnTimeout,
                    base::Unretained(this)));
   }
 }
 
 void KioskModeIdleAppNameNotification::OnTimeout() {
   show_notification_upon_next_user_activity_ = true;
 }
 
 }  // namespace chromeos