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

chrome/browser/chromeos/login/screens/mock_network_screen.h

 // 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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_LOGIN_SCREENS_MOCK_NETWORK_SCREEN_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_SCREENS_MOCK_NETWORK_SCREEN_H_
 
 #include "chrome/browser/chromeos/login/screens/base_screen_delegate.h"
 #include "chrome/browser/chromeos/login/screens/network_screen.h"
 #include "chrome/browser/chromeos/login/screens/network_view.h"
 #include "testing/gmock/include/gmock/gmock.h"
 
 namespace chromeos {
 
 class MockNetworkScreen : public NetworkScreen {
  public:
   MockNetworkScreen(BaseScreenDelegate* base_screen_delegate,
                     Delegate* delegate,
                     NetworkView* view);
-  virtual ~MockNetworkScreen();
+  ~MockNetworkScreen() override;
 
   MOCK_METHOD0(Show, void());
   MOCK_METHOD0(Hide, void());
 };
 
 class MockNetworkView : public NetworkView {
  public:
   MockNetworkView();
-  virtual ~MockNetworkView();
+  ~MockNetworkView() override;
 
-  virtual void Bind(NetworkModel& model) override;
-  virtual void Unbind() override;
+  void Bind(NetworkModel& model) override;
+  void Unbind() override;
 
   MOCK_METHOD1(MockBind, void(NetworkModel& model));
   MOCK_METHOD0(MockUnbind, void());
   MOCK_METHOD0(PrepareToShow, void());
   MOCK_METHOD0(Show, void());
   MOCK_METHOD0(Hide, void());
   MOCK_METHOD1(ShowError, void(const base::string16& message));
   MOCK_METHOD0(ClearErrors, void());
   MOCK_METHOD0(StopDemoModeDetection, void());
   MOCK_METHOD2(ShowConnectingStatus,
                void(bool connecting, const base::string16& network_id));
   MOCK_METHOD1(EnableContinue, void(bool enabled));
   MOCK_METHOD0(ReloadLocalizedContent, void());
 
  private:
   NetworkModel* model_;
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_SCREENS_MOCK_NETWORK_SCREEN_H_