Update {virtual,override} to follow C++11 style in chrome.

chrome/browser/ui/startup/default_browser_prompt_win.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 "chrome/browser/ui/startup/default_browser_prompt.h"
 
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/shell_integration.h"
 #include "chrome/browser/ui/browser.h"
@@ skipping 20 matching lines @@
   }
 
  private:
   explicit SetMetroBrowserFlowLauncher(Profile* profile)
       : profile_(profile) {
     registrar_.Add(this, content::NOTIFICATION_LOAD_COMPLETED_MAIN_FRAME,
                    content::NotificationService::AllSources());
   }
 
   // content::NotificationObserver override:
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) override;
+  void Observe(int type,
+               const content::NotificationSource& source,
+               const content::NotificationDetails& details) override;
 
   content::NotificationRegistrar registrar_;
   Profile* profile_;
 
   DISALLOW_COPY_AND_ASSIGN(SetMetroBrowserFlowLauncher);
 };
 
 void SetMetroBrowserFlowLauncher::Observe(
     int type,
     const content::NotificationSource& source,
@@ skipping 26 matching lines @@
 
   if (show_status) {
     startup_metric_utils::SetNonBrowserUIDisplayed();
     SetMetroBrowserFlowLauncher::LaunchSoon(profile);
   }
 
   return show_status;
 }
 
 }  // namespace chrome