Fix error in standalone/io/secure_socket_bad_data_test.

tests/standalone/io/secure_socket_bad_data_test.dart

 // Copyright (c) 2013, 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
 // VMOptions=--short_socket_write
 // VMOptions=--short_socket_read --short_socket_write
 
 import "package:expect/expect.dart";
@@ skipping 71 matching lines @@
       Expect.isTrue(e.toString().contains(
           'received a record with an incorrect Message Authentication Code'));
       completer.complete(null);
     });
     return completer.future;
   }
 
   Future<RawSocket> runClient(List sockets) {
     RawSocket baseSocket = sockets[0];
     RawSecureSocket socket = sockets[1];
     final completer = new Completer();

[Anders Johnsen, 2013/07/04 11:36:56]

Make completer var and test for null?

+    bool completed = false;
+    void tryComplete() {
+      if (!completed) {
+        completed = true;
+        completer.complete(null);
+      }
+    }
     final data = createTestData();
     int bytesWritten = 0;
     socket.listen((event) {
       switch (event) {
         case RawSocketEvent.READ:
           Expect.fail('READ event received');
           break;
         case RawSocketEvent.WRITE:
           if (bytesWritten < data.length) {
             bytesWritten +=  socket.write(data, bytesWritten);
           }
           if (bytesWritten < data.length) {
             socket.writeEventsEnabled = true;
           }
           if (bytesWritten == data.length) {
             baseSocket.write(data, 0, 300);
             socket.shutdown(SocketDirection.SEND);
           }
           break;
         case RawSocketEvent.READ_CLOSED:
-          completer.complete(null);
+          tryComplete();
           break;
         default: throw "Unexpected event $event";
       }
     },
     onError: (e) {
       Expect.isTrue(e is IOException);
-      completer.complete(null);
+      tryComplete();
     });
     return completer.future;
   }
 
 
   Future<List> connectClient(int port) =>
     RawSocket.connect(HOST_NAME, port)
     .then((socket) =>
       (hostnameInConnect ? RawSecureSocket.secure(socket)
                          : RawSecureSocket.secure(socket, host: HOST_NAME))
@@ skipping 18 matching lines @@
 
 main() {
   Path scriptDir = new Path(Platform.script).directoryPath;
   Path certificateDatabase = scriptDir.append('pkcert');
   SecureSocket.initialize(database: certificateDatabase.toNativePath(),
                           password: 'dartdart',
                           useBuiltinRoots: false);
   test(false);
   test(true);
 }