Update {virtual,override} to follow C++11 style in ppapi.

ppapi/proxy/tcp_server_socket_private_resource.h

Index: ppapi/proxy/tcp_server_socket_private_resource.h
diff --git a/ppapi/proxy/tcp_server_socket_private_resource.h b/ppapi/proxy/tcp_server_socket_private_resource.h
index dad3fd89ab8e26a642ec3602da4824cfb32a07bd..055b3b05db24a5de89caecae89d4f5d8ce1ef817 100644
--- a/ppapi/proxy/tcp_server_socket_private_resource.h
+++ b/ppapi/proxy/tcp_server_socket_private_resource.h
@@ -21,20 +21,20 @@ class PPAPI_PROXY_EXPORT TCPServerSocketPrivateResource
       public thunk::PPB_TCPServerSocket_Private_API {
  public:
   TCPServerSocketPrivateResource(Connection connection, PP_Instance instance);
-  virtual ~TCPServerSocketPrivateResource();
+  ~TCPServerSocketPrivateResource() override;
 
   // PluginResource implementation.
-  virtual thunk::PPB_TCPServerSocket_Private_API*
-      AsPPB_TCPServerSocket_Private_API() override;
+  thunk::PPB_TCPServerSocket_Private_API* AsPPB_TCPServerSocket_Private_API()
+      override;
 
   // PPB_TCPServerSocket_Private_API implementation.
-  virtual int32_t Listen(const PP_NetAddress_Private* addr,
-                         int32_t backlog,
-                         scoped_refptr<TrackedCallback> callback) override;
-  virtual int32_t Accept(PP_Resource* tcp_socket,
-                         scoped_refptr<TrackedCallback> callback) override;
-  virtual int32_t GetLocalAddress(PP_NetAddress_Private* addr) override;
-  virtual void StopListening() override;
+  int32_t Listen(const PP_NetAddress_Private* addr,
+                 int32_t backlog,
+                 scoped_refptr<TrackedCallback> callback) override;
+  int32_t Accept(PP_Resource* tcp_socket,
+                 scoped_refptr<TrackedCallback> callback) override;
+  int32_t GetLocalAddress(PP_NetAddress_Private* addr) override;
+  void StopListening() override;
 
  private:
   enum State {