Standardize usage of virtual/override/final in content/browser/

content/browser/battery_status/battery_status_manager_mac.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 "content/browser/battery_status/battery_status_manager.h"
 
 #include <CoreFoundation/CoreFoundation.h>
 #include <IOKit/ps/IOPowerSources.h>
 #include <IOKit/ps/IOPSKeys.h>
 #include <vector>
@@ skipping 236 matching lines @@
   base::ScopedCFTypeRef<CFRunLoopSourceRef> notifier_run_loop_source_;
 
   DISALLOW_COPY_AND_ASSIGN(BatteryStatusObserver);
 };
 
 class BatteryStatusManagerMac : public BatteryStatusManager {
  public:
   explicit BatteryStatusManagerMac(const BatteryCallback& callback)
       : notifier_(new BatteryStatusObserver(callback)) {}
 
-  virtual ~BatteryStatusManagerMac() {
-    notifier_->Stop();
-  }
+  ~BatteryStatusManagerMac() override { notifier_->Stop(); }
 
   // BatteryStatusManager:
-  virtual bool StartListeningBatteryChange() override {
+  bool StartListeningBatteryChange() override {
     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
     notifier_->Start();
     return true;
   }
 
-  virtual void StopListeningBatteryChange() override {
+  void StopListeningBatteryChange() override {
     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
     notifier_->Stop();
   }
 
  private:
   scoped_refptr<BatteryStatusObserver> notifier_;
 
   DISALLOW_COPY_AND_ASSIGN(BatteryStatusManagerMac);
 };
 
 } // end namespace
 
 // static
 scoped_ptr<BatteryStatusManager> BatteryStatusManager::Create(
     const BatteryStatusService::BatteryUpdateCallback& callback) {
   return scoped_ptr<BatteryStatusManager>(
       new BatteryStatusManagerMac(callback));
 }
 
 }  // namespace content