Standardize usage of virtual/override/final specifiers.

net/proxy/proxy_config_service_linux.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 NET_PROXY_PROXY_CONFIG_SERVICE_LINUX_H_
 #define NET_PROXY_PROXY_CONFIG_SERVICE_LINUX_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 262 matching lines @@
 
   // Thin wrapper shell around Delegate.
 
   // Usual constructor
   ProxyConfigServiceLinux();
   // For testing: take alternate setting and env var getter implementations.
   explicit ProxyConfigServiceLinux(base::Environment* env_var_getter);
   ProxyConfigServiceLinux(base::Environment* env_var_getter,
                           SettingGetter* setting_getter);
 
-  virtual ~ProxyConfigServiceLinux();
+  ~ProxyConfigServiceLinux() override;
 
   void SetupAndFetchInitialConfig(
       const scoped_refptr<base::SingleThreadTaskRunner>& glib_task_runner,
       const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
       const scoped_refptr<base::SingleThreadTaskRunner>& file_task_runner) {
     delegate_->SetUpAndFetchInitialConfig(glib_task_runner,
                                           io_task_runner,
                                           file_task_runner);
   }
   void OnCheckProxyConfigSettings() {
     delegate_->OnCheckProxyConfigSettings();
   }
 
   // ProxyConfigService methods:
   // Called from IO thread.
-  virtual void AddObserver(Observer* observer) override;
-  virtual void RemoveObserver(Observer* observer) override;
-  virtual ProxyConfigService::ConfigAvailability GetLatestProxyConfig(
+  void AddObserver(Observer* observer) override;
+  void RemoveObserver(Observer* observer) override;
+  ProxyConfigService::ConfigAvailability GetLatestProxyConfig(
       ProxyConfig* config) override;
 
  private:
   scoped_refptr<Delegate> delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(ProxyConfigServiceLinux);
 };
 
 }  // namespace net
 
 #endif  // NET_PROXY_PROXY_CONFIG_SERVICE_LINUX_H_