Add remotePort getter to Socket.

runtime/bin/socket_impl.dart

 // Copyright (c) 2012, 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.
 
 
 class _SocketBase {
   // Bit flags used when communicating between the eventhandler and
   // dart code. The EVENT flags are used to indicate events of
   // interest when sending a message from dart code to the
   // eventhandler. When receiving a message from the eventhandler the
@@ skipping 531 matching lines @@
       _onWrite = null;
     } else {
       if (_seenFirstOutEvent) {
         _onWrite = _clientWriteHandler;
       } else {
         _onWrite = firstWriteHandler;
       }
     }
   }
 
+  int get remotePort() {
+    if (_remotePort === null) {
+      _remotePort = _getRemotePort();
+    }
+    return _remotePort;
+  }
+
+  int _getRemotePort() native "Socket_GetRemotePort";
+
   static SendPort _newServicePort() native "Socket_NewServicePort";
 
   static void _ensureSocketService() {
     if (_socketService == null) {
       _socketService = _Socket._newServicePort();
     }
   }
 
   bool _seenFirstOutEvent = false;
   bool _pipe = false;
   Function _clientConnectHandler;
   Function _clientWriteHandler;
   SocketInputStream _inputStream;
   SocketOutputStream _outputStream;
+  int _remotePort;
   static SendPort _socketService;
 }