Add 'owner' field to sockets, that point to a potential IO resource using that Socket.

sdk/lib/io/secure_server_socket.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.
 
 part of dart.io;
 
 /**
  * The [SecureServerSocket] is a server socket, providing a stream of high-level
  * [Socket]s.
  *
@@ skipping 86 matching lines @@
   /**
    * Returns the address used by this socket.
    */
   InternetAddress get address => _socket.address;
 
   /**
    * Closes the socket. The returned future completes when the socket
    * is fully closed and is no longer bound.
    */
   Future<SecureServerSocket> close() => _socket.close().then((_) => this);
+
+  void set _owner(owner) { _socket._owner = owner; }
 }
 
 
 /**
  * The RawSecureServerSocket is a server socket, providing a stream of low-level
  * [RawSecureSocket]s.
  *
  * See [RawSecureSocket] for more info.
  */
 class RawSecureServerSocket extends Stream<RawSecureSocket> {
@@ skipping 154 matching lines @@
 
   void _onSubscriptionStateChange() {
     if (_controller.hasListener) {
       _subscription = _socket.listen(_onData,
                                      onDone: _onDone,
                                      onError: _onError);
     } else {
       close();
     }
   }
+
+  void set _owner(owner) { (_socket as dynamic)._owner = owner; }
 }