Standardize usage of virtual/override/final in net/

net/http/http_network_layer.h

Index: net/http/http_network_layer.h
diff --git a/net/http/http_network_layer.h b/net/http/http_network_layer.h
index 58b02f2608530934b3b312d19605f9cf124bb220..13b0c79b8c2c96481d58096d35e1dc82e0212c13 100644
--- a/net/http/http_network_layer.h
+++ b/net/http/http_network_layer.h
@@ -28,7 +28,7 @@ class NET_EXPORT HttpNetworkLayer
   // Construct a HttpNetworkLayer with an existing HttpNetworkSession which
   // contains a valid ProxyService.
   explicit HttpNetworkLayer(HttpNetworkSession* session);
-  virtual ~HttpNetworkLayer();
+  ~HttpNetworkLayer() override;
 
   // Create a transaction factory that instantiate a network layer over an
   // existing network session. Network session contains some valuable
@@ -43,14 +43,14 @@ class NET_EXPORT HttpNetworkLayer
   static void ForceAlternateProtocol();
 
   // HttpTransactionFactory methods:
-  virtual int CreateTransaction(RequestPriority priority,
-                                scoped_ptr<HttpTransaction>* trans) override;
-  virtual HttpCache* GetCache() override;
-  virtual HttpNetworkSession* GetSession() override;
+  int CreateTransaction(RequestPriority priority,
+                        scoped_ptr<HttpTransaction>* trans) override;
+  HttpCache* GetCache() override;
+  HttpNetworkSession* GetSession() override;
 
   // base::PowerObserver methods:
-  virtual void OnSuspend() override;
-  virtual void OnResume() override;
+  void OnSuspend() override;
+  void OnResume() override;
 
  private:
   const scoped_refptr<HttpNetworkSession> session_;