Use native wrapper fields to store socket ids.

runtime/bin/socket_stream_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 _SocketInputStream implements SocketInputStream {
   _SocketInputStream(Socket socket) : _socket = socket {
-    if (_socket._id == -1) _closed = true;
+    if (_socket._closed) _closed = true;
     _socket.onClosed = _onClosed;
   }
 
   List<int> read([int len]) {
     int bytesToRead = available();
     if (bytesToRead == 0) return null;
     if (len !== null) {
       if (len <= 0) {
         throw new StreamException("Illegal length $len");
       } else if (bytesToRead > len) {
@@ skipping 203 matching lines @@
     }
   }
 
   Socket _socket;
   _BufferList _pendingWrites;
   Function _onNoPendingWrites;
   Function _onClosed;
   bool _closing = false;
   bool _closed = false;
 }