Standardize usage of virtual/override/final in mojo/

mojo/spy/spy_server_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_SPY_SPY_SERVER_IMPL_H_
 #define MOJO_SPY_SPY_SERVER_IMPL_H_
 
 #include <map>
 
 #include "base/memory/ref_counted.h"
 #include "mojo/public/cpp/system/core.h"
 #include "mojo/spy/public/spy.mojom.h"
 #include "url/gurl.h"
 
 namespace mojo {
 
 class SpyServerImpl :
     public base::RefCounted<SpyServerImpl>,
     public InterfaceImpl<spy_api::SpyServer> {
  public:
   SpyServerImpl();
 
   // spy_api::SpyServer implementation.
-  virtual void StartSession(
-      spy_api::VersionPtr version,
-      const mojo::Callback<void(spy_api::Result,
-                                mojo::String)>& callback) override;
+  void StartSession(spy_api::VersionPtr version,
+                    const mojo::Callback<void(spy_api::Result, mojo::String)>&
+                        callback) override;
 
-  virtual void StopSession(
+  void StopSession(
       const mojo::Callback<void(spy_api::Result)>& callback) override;
 
-  virtual void TrackConnection(
+  void TrackConnection(
       uint32_t id,
       spy_api::ConnectionOptions options,
       const mojo::Callback<void(spy_api::Result)>& callback) override;
 
-  virtual void OnConnectionError() override;
+  void OnConnectionError() override;
 
   // SpyServerImpl own methods.
   void OnIntercept(const GURL& url);
 
   ScopedMessagePipeHandle ServerPipe();
 
  private:
   friend class base::RefCounted<SpyServerImpl>;
-  virtual ~SpyServerImpl();
+  ~SpyServerImpl() override;
 
   // Item models the entities that we track by IDs.
   struct Item;
 
   MessagePipe pipe_;
   bool has_session_;
   std::map<uint32_t, Item*> items_;
 };
 
 }  // namespace mojo
 
 #endif  // MOJO_SPY_SPY_SERVER_IMPL_H_