Standardize usage of virtual/override/final in chrome/browser/

chrome/browser/feedback/system_logs/log_sources/chrome_internal_log_source.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_FEEDBACK_SYSTEM_LOGS_LOG_SOURCES_CHROME_INTERNAL_LOG_SOURCE_H_
 #define CHROME_BROWSER_FEEDBACK_SYSTEM_LOGS_LOG_SOURCES_CHROME_INTERNAL_LOG_SOURCE_H_
 
 #include "chrome/browser/feedback/system_logs/system_logs_fetcher_base.h"
 
 namespace system_logs {
 
 // Fetches internal Chrome logs.
 class ChromeInternalLogSource : public SystemLogsSource {
  public:
   ChromeInternalLogSource();
-  virtual ~ChromeInternalLogSource();
+  ~ChromeInternalLogSource() override;
 
   // SystemLogsSource override.
-  virtual void Fetch(const SysLogsSourceCallback& request) override;
+  void Fetch(const SysLogsSourceCallback& request) override;
 
  private:
   void PopulateSyncLogs(SystemLogsResponse* response);
   void PopulateExtensionInfoLogs(SystemLogsResponse* response);
 
   DISALLOW_COPY_AND_ASSIGN(ChromeInternalLogSource);
 };
 
 }  // namespace system_logs
 
 #endif  // CHROME_BROWSER_FEEDBACK_SYSTEM_LOGS_LOG_SOURCES_CHROME_INTERNAL_LOG_SOURCE_H_