dart:io | Ensure that close() returns a Future<this> on all (Raw)?(Secure)?(Server)?Socket classes …

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 77 matching lines @@
                           onDone: onDone,
                           cancelOnError: cancelOnError);
   }
 
   /**
    * Returns the port used by this socket.
    */
   int get port => _socket.port;
 
   /**
-   * Closes the socket.
+   * Closes the socket. The returned future completes when the socket
+   * is fully closed and is no longer bound.
    */
-  void close() => _socket.close();
+  Future<SecureServerSocket> close() => _socket.close().then((_) => this);
 }
 
 
 /**
  * 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 86 matching lines @@
                                      onDone: onDone,
                                      cancelOnError: cancelOnError);
   }
 
   /**
    * Returns the port used by this socket.
    */
   int get port => _socket.port;
 
   /**
-   * Closes the socket.
+   * Closes the socket. The returned future completes when the socket
+   * is fully closed and is no longer bound.
    */
-  void close() {
+  Future<RawSecureServerSocket> close() {
     _closed = true;
-    _socket.close();
+    return _socket.close().then((_) => this);
   }
 
   void _onData(RawSocket connection) {
     var remotePort;
     try {
       remotePort = connection.remotePort;
     } catch (e) {
       // If connection is already closed, remotePort throws an exception.
       // Do nothing - connection is closed.
       return;
@@ skipping 40 matching lines @@
       _subscription = _socket.listen(_onData,
                                      onDone: _onDone,
                                      onError: _onError);
     } else {
       close();
     }
   }
 }