dart:io | Fix handling of exceptions from onBadCertificate callback.

tests/standalone/io/secure_socket_renegotiate_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.
 
 // This test verifies that client certificates work, if the client and server
 // are in separate processes, and that connection renegotiation works, and
 // can request a client certificate to be sent.
 
 import "package:expect/expect.dart";
-import "package:path/path.dart" as path;
+import "package:path/path.dart";
 import "dart:async";
 import "dart:io";
 
 const HOST_NAME = "localhost";
 const CERTIFICATE = "localhost_cert";
 
 
-String certificateDatabase() =>
-    path.join(path.dirname(new Options().script), 'pkcert', '');
+String certificateDatabase() => join(dirname(new Options().script), 'pkcert');
 
 
 Future<SecureServerSocket> runServer() {
   SecureSocket.initialize(database: certificateDatabase(),
-      password: 'dartdart');
+                          password: 'dartdart');
 
   return SecureServerSocket.bind(HOST_NAME, 0, CERTIFICATE)
     .then((SecureServerSocket server) {
       server.listen((SecureSocket socket) {
         Expect.isNull(socket.peerCertificate);
 
         StreamIterator<String> input =
             new StreamIterator(socket.transform(new StringDecoder())
                                      .transform(new LineTransformer()));
         input.moveNext().then((success) {
@@ skipping 41 matching lines @@
           if (result.exitCode != 0) {
             print("Client failed, stdout:");
             print(result.stdout);
             print("  stderr:");
             print(result.stderr);
             Expect.fail('Client subprocess exit code: ${result.exitCode}');
           }
         });
     });
 }