Standardize usage of virtual/override/final specifiers.

chrome/browser/ui/webui/certificate_viewer_ui.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_UI_WEBUI_CERTIFICATE_VIEWER_UI_H_
 #define CHROME_BROWSER_UI_WEBUI_CERTIFICATE_VIEWER_UI_H_
 
 #include "chrome/browser/ui/webui/constrained_web_dialog_ui.h"
 #include "ui/web_dialogs/web_dialog_ui.h"
 
 // The WebUI for chrome://view-cert-dialog
 class CertificateViewerModalDialogUI : public ui::WebDialogUI {
  public:
   explicit CertificateViewerModalDialogUI(content::WebUI* web_ui);
-  virtual ~CertificateViewerModalDialogUI();
+  ~CertificateViewerModalDialogUI() override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(CertificateViewerModalDialogUI);
 };
 
 // The WebUI for chrome://view-cert
 class CertificateViewerUI : public ConstrainedWebDialogUI {
  public:
   explicit CertificateViewerUI(content::WebUI* web_ui);
-  virtual ~CertificateViewerUI();
+  ~CertificateViewerUI() override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(CertificateViewerUI);
 };
 
 #endif  // CHROME_BROWSER_UI_WEBUI_CERTIFICATE_VIEWER_UI_H_