Standardize usage of virtual/override/final in mojo/

mojo/public/cpp/application/service_provider_impl.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 MOJO_PUBLIC_APPLICATION_SERVICE_PROVIDER_IMPL_H_
 #define MOJO_PUBLIC_APPLICATION_SERVICE_PROVIDER_IMPL_H_
 
 #include "mojo/public/cpp/application/lib/service_connector.h"
 #include "mojo/public/interfaces/application/service_provider.mojom.h"
 
 namespace mojo {
 namespace internal {
 class WeakServiceProvider;
 class ServiceConnectorBase;
 }
 
 // Implements a registry that can be used to expose services to another app.
 class ServiceProviderImpl : public InterfaceImpl<ServiceProvider> {
  public:
   ServiceProviderImpl();
-  virtual ~ServiceProviderImpl();
+  ~ServiceProviderImpl() override;
 
   template <typename Interface>
   void AddService(InterfaceFactory<Interface>* factory) {
     AddServiceConnector(
         new internal::InterfaceFactoryConnector<Interface>(factory));
   }
 
   // Returns an instance of a ServiceProvider that weakly wraps this impl's
   // connection to some other app. Whereas the lifetime of an instance of
   // ServiceProviderImpl is bound to the lifetime of the pipe it
   // encapsulates, the lifetime of the ServiceProvider instance returned by this
   // method is assumed by the caller. After the pipe is closed
   // ConnectToService() calls on this object will be silently dropped.
   // This method must only be called once per ServiceProviderImpl.
   ServiceProvider* CreateRemoteServiceProvider();
 
  private:
   typedef std::map<std::string, internal::ServiceConnectorBase*>
       NameToServiceConnectorMap;
 
   friend class internal::WeakServiceProvider;
 
   // Overridden from ServiceProvider:
-  virtual void ConnectToService(const String& service_name,
-                                ScopedMessagePipeHandle client_handle) override;
+  void ConnectToService(const String& service_name,
+                        ScopedMessagePipeHandle client_handle) override;
 
   // Overridden from InterfaceImpl:
-  virtual void OnConnectionError() override;
+  void OnConnectionError() override;
 
   void AddServiceConnector(internal::ServiceConnectorBase* service_connector);
   void RemoveServiceConnector(
       internal::ServiceConnectorBase* service_connector);
 
   void ClearRemote();
 
   NameToServiceConnectorMap service_connectors_;
 
   internal::WeakServiceProvider* remote_;
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(ServiceProviderImpl);
 };
 
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_APPLICATION_SERVICE_PROVIDER_IMPL_H_