Add a callback to SecureSocket for certificates that fail to be authenticated.

tests/standalone/io/secure_server_stream_test.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.
 
 import "dart:io";
+import "dart:isolate";
 
 const SERVER_ADDRESS = "127.0.0.1";
 const HOST_NAME = "localhost";
 
 class SecureTestServer {
   void onConnection(Socket connection) {
     numConnections++;
     var input = connection.inputStream;
     String received = "";
     input.onData = () {
@@ skipping 56 matching lines @@
   String name;
   SecureSocket socket;
   String reply;
 }
 
 Function EndTest;
 
 const CLIENT_NAMES = const ['able', 'baker', 'camera', 'donut', 'echo'];
 
 void main() {
+  ReceivePort keepAlive = new ReceivePort();
   Path scriptDir = new Path.fromNative(new Options().script).directoryPath;
   Path certificateDatabase = scriptDir.append('pkcert');
   SecureSocket.initialize(database: certificateDatabase.toNativePath(),
                           password: 'dartdart');
 
   var server = new SecureTestServer();
   int port = server.start();
 
   EndTest = () {
     Expect.equals(CLIENT_NAMES.length, server.numConnections);
     server.stop();
+    keepAlive.close();
   };
 
   for (var x in CLIENT_NAMES) {
     new SecureTestClient(port, x);
   }
 }