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

chrome/browser/search/contextual_search_promo_source_android.h

 // 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.
 
 #ifndef CHROME_BROWSER_SEARCH_CONTEXTUAL_SEARCH_PROMO_SOURCE_ANDROID_H_
 #define CHROME_BROWSER_SEARCH_CONTEXTUAL_SEARCH_PROMO_SOURCE_ANDROID_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "content/public/browser/url_data_source.h"
 
 // Serves HTML for displaying the contextual search first-run promo.
 class ContextualSearchPromoSourceAndroid : public content::URLDataSource {
  public:
   ContextualSearchPromoSourceAndroid();
-  virtual ~ContextualSearchPromoSourceAndroid();
+  ~ContextualSearchPromoSourceAndroid() override;
 
  protected:
   // Overridden from content::URLDataSource:
-  virtual void StartDataRequest(
+  void StartDataRequest(
       const std::string& path_and_query,
       int render_process_id,
       int render_frame_id,
       const content::URLDataSource::GotDataCallback& callback) override;
-  virtual std::string GetSource() const override;
-  virtual std::string GetMimeType(
-      const std::string& path_and_query) const override;
-  virtual bool ShouldDenyXFrameOptions() const override;
-  virtual bool ShouldAddContentSecurityPolicy() const override;
+  std::string GetSource() const override;
+  std::string GetMimeType(const std::string& path_and_query) const override;
+  bool ShouldDenyXFrameOptions() const override;
+  bool ShouldAddContentSecurityPolicy() const override;
 
   // Sends unmodified resource bytes.
   void SendResource(
       int resource_id,
       const content::URLDataSource::GotDataCallback& callback);
 
   // Sends the config JS resource.
   void SendConfigResource(
       const content::URLDataSource::GotDataCallback& callback);
 
   // Sends HTML with localized strings.
   void SendHtmlWithStrings(
     const content::URLDataSource::GotDataCallback& callback);
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ContextualSearchPromoSourceAndroid);
 };
 
 #endif  // CHROME_BROWSER_SEARCH_CONTEXTUAL_SEARCH_PROMO_SOURCE_ANDROID_H_