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

tests/standalone/io/secure_socket_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.
 //
 // VMOptions=
 // VMOptions=--short_socket_read
 // The --short_socket_write option does not work with external server
 // www.google.dk.  Add this to the test when we have secure server sockets.
 // See TODO below.
 
 #import("dart:isolate");
 #import("dart:io");
 
 void WriteAndClose(Socket socket, String message) {
   var data = message.charCodes;
   int written = 0;
   void write() {
     written += socket.writeList(data, written, data.length - written);
     if (written < data.length) {
       socket.onWrite = write;
     } else {
       socket.close(true);
     }
   }
   write();
 }
 
 void main() {
+  ReceivePort keepAlive = new ReceivePort();
   SecureSocket.initialize();
   // TODO(3593): Use a Dart HTTPS server for this test.
   // When we use a Dart HTTPS server, allow --short_socket_write. The flag
   // causes fragmentation of the client hello message, which doesn't seem to
   // work with www.google.dk.
   var secure = new SecureSocket("www.google.dk", 443);
   List<String> chunks = <String>[];
   secure.onConnect = () {
     WriteAndClose(secure, "GET / HTTP/1.0\r\nHost: www.google.dk\r\n\r\n");
   };
   var useReadList;  // Mutually recursive onData callbacks.
   void useRead() {
     var data = secure.read();
     var received = new String.fromCharCodes(data);
     chunks.add(received);
     secure.onData = useReadList;
   }
   useReadList = () {
     var buffer = new List(2000);
     int len = secure.readList(buffer, 0, 2000);
     var received = new String.fromCharCodes(buffer.getRange(0, len));
     chunks.add(received);
     secure.onData = useRead;
   };
   secure.onData = useRead;
   secure.onClosed = () {
     String fullPage = Strings.concatAll(chunks);
     Expect.isTrue(fullPage.contains('</body></html>'));
+    keepAlive.close();
   };
 }