Update {virtual,override,final} to follow C++11 style chrome/browser/ui/webui/chromeos.

chrome/browser/ui/webui/chromeos/slow_trace_ui.h

 // Copyright 2013 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_CHROMEOS_SLOW_TRACE_UI_H_
 #define CHROME_BROWSER_UI_WEBUI_CHROMEOS_SLOW_TRACE_UI_H_
 
 #include <string>
 
 #include "base/compiler_specific.h"
@@ skipping 10 matching lines @@
 
 // This class provides the source for chrome://slow_trace/.  It needs to be a
 // separate handler that chrome://slow, because URLDataSource and
 // WebUIDataSource are not descended from each other, and WebUIDataSource
 // doesn't allow the MimeType to be dynamically specified.
 class SlowTraceSource : public content::URLDataSource {
  public:
   SlowTraceSource();
 
   // content::URLDataSource implementation.
-  virtual std::string GetSource() const override;
-  virtual void StartDataRequest(
+  std::string GetSource() const override;
+  void StartDataRequest(
       const std::string& path,
       int render_process_id,
       int render_frame_id,
       const content::URLDataSource::GotDataCallback& callback) override;
-  virtual std::string GetMimeType(const std::string& path) const override;
+  std::string GetMimeType(const std::string& path) const override;
 
  private:
-  virtual ~SlowTraceSource();
+  ~SlowTraceSource() override;
 
   void OnGetTraceData(const content::URLDataSource::GotDataCallback& callback,
                       scoped_refptr<base::RefCountedString> trace_data);
 
   DISALLOW_COPY_AND_ASSIGN(SlowTraceSource);
 };
 
 class SlowTraceController : public content::WebUIController {
  public:
   explicit SlowTraceController(content::WebUI* web_ui);
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SlowTraceController);
 };
 
 } // namespace chromeos
 
 #endif  // CHROME_BROWSER_UI_WEBUI_CHROMEOS_SLOW_TRACE_UI_H_