Added Socket::Close() function.

runtime/bin/socket.h

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef BIN_SOCKET_H_
 #define BIN_SOCKET_H_
 
 #include "bin/builtin.h"
 #include "bin/utils.h"
 
@@ skipping 22 matching lines @@
   static bool Initialize();
   static intptr_t Available(intptr_t fd);
   static int Read(intptr_t fd, void* buffer, intptr_t num_bytes);
   static int Write(intptr_t fd, const void* buffer, intptr_t num_bytes);
   static intptr_t CreateConnect(const char* host, const intptr_t port);
   static intptr_t GetPort(intptr_t fd);
   static bool GetRemotePeer(intptr_t fd, char* host, intptr_t* port);
   static void GetError(intptr_t fd, OSError* os_error);
   static int GetType(intptr_t fd);
   static intptr_t GetStdioHandle(int num);
+  static void Close(intptr_t fd);
 
   // Perform a IPv4 hostname lookup. Returns the hostname string in
   // IPv4 dotted-decimal format.
   static const char* LookupIPv4Address(char* host, OSError** os_error);
 
   static Dart_Port GetServicePort();
 
   static Dart_Handle SetSocketIdNativeField(Dart_Handle socket, intptr_t id);
   static Dart_Handle GetSocketIdNativeField(Dart_Handle socket, intptr_t* id);
 
@@ skipping 21 matching lines @@
   //   -5: invalid bindAddress
   static intptr_t CreateBindListen(const char* bindAddress,
                                    intptr_t port,
                                    intptr_t backlog);
 
   DISALLOW_ALLOCATION();
   DISALLOW_IMPLICIT_CONSTRUCTORS(ServerSocket);
 };
 
 #endif  // BIN_SOCKET_H_