Split secure_server_client_certificate test in two, because of session cache.

tests/standalone/io/secure_server_client_certificate_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.
 
 import "dart:async";
 import "dart:io";
 
 import "package:async_helper/async_helper.dart";
 import "package:expect/expect.dart";
 import "package:path/path.dart";
 
 const HOST_NAME = "localhost";
 const CERTIFICATE = "localhost_cert";
 
-void testClientCertificate() {
-  asyncStart();
+Future testClientCertificate() {
+  var completer = new Completer();
   SecureServerSocket.bind(HOST_NAME,
                           0,
                           CERTIFICATE,
                           requestClientCertificate: true).then((server) {
     var clientEndFuture = SecureSocket.connect(HOST_NAME,
                                                server.port,
                                                sendClientCertificate: true);
     server.listen((serverEnd) {
       X509Certificate certificate = serverEnd.peerCertificate;
       Expect.isNotNull(certificate);
       Expect.equals("CN=localhost", certificate.subject);
       Expect.equals("CN=myauthority", certificate.issuer);
       clientEndFuture.then((clientEnd) {
         X509Certificate certificate = clientEnd.peerCertificate;
         Expect.isNotNull(certificate);
         Expect.equals("CN=localhost", certificate.subject);
         Expect.equals("CN=myauthority", certificate.issuer);
         clientEnd.close();
         serverEnd.close();
         server.close();
-        asyncEnd();
+        completer.complete();
       });
     });
   });
+  return completer.future;
 }
 
-void testRequiredClientCertificate() {
-  asyncStart();
+Future testRequiredClientCertificate() {
+  var completer = new Completer();
   SecureServerSocket.bind(HOST_NAME,
                           0,
                           CERTIFICATE,
                           requireClientCertificate: true).then((server) {
     var clientEndFuture = SecureSocket.connect(HOST_NAME,
                                                server.port,
                                                sendClientCertificate: true);
     server.listen((serverEnd) {
       X509Certificate certificate = serverEnd.peerCertificate;
       Expect.isNotNull(certificate);
       Expect.equals("CN=localhost", certificate.subject);
       Expect.equals("CN=myauthority", certificate.issuer);
       clientEndFuture.then((clientEnd) {
         X509Certificate certificate = clientEnd.peerCertificate;
         Expect.isNotNull(certificate);
         Expect.equals("CN=localhost", certificate.subject);
         Expect.equals("CN=myauthority", certificate.issuer);
         clientEnd.close();
         serverEnd.close();
         server.close();
-        asyncEnd();
+        completer.complete();
       });
     });
   });
-}
-
-void testNoClientCertificate() {
-  asyncStart();
-  SecureServerSocket.bind(HOST_NAME,
-                          0,
-                          CERTIFICATE,
-                          requestClientCertificate: true).then((server) {
-    var clientEndFuture = SecureSocket.connect(HOST_NAME,
-                                               server.port);
-    server.listen((serverEnd) {
-      X509Certificate certificate = serverEnd.peerCertificate;
-      Expect.isNull(certificate);
-      clientEndFuture.then((clientEnd) {
-        clientEnd.close();
-        serverEnd.close();
-        server.close();
-        asyncEnd();
-      });
-    });
-  });
-}
-
-void testNoRequiredClientCertificate() {
-  asyncStart();
-  bool clientError = false;
-  SecureServerSocket.bind(HOST_NAME,
-                          0,
-                          CERTIFICATE,
-                          requireClientCertificate: true).then((server) {
-    Future clientDone = SecureSocket.connect(HOST_NAME, server.port)
-      .catchError((e) { clientError = true; });
-    server.listen((serverEnd) {
-      Expect.fail("Got a unverifiable connection");
-    },
-    onError: (e) {
-      clientDone.then((_) {
-        Expect.isTrue(clientError);
-        server.close();
-        asyncEnd();
-      });
-    });
-  });
+  return completer.future;
 }
 
 void main() {
   String certificateDatabase = join(dirname(Platform.script), 'pkcert');
   SecureSocket.initialize(database: certificateDatabase,
                           password: 'dartdart',
                           useBuiltinRoots: false);
 
-  testClientCertificate();
-  testRequiredClientCertificate();
-  testNoClientCertificate();
-  testNoRequiredClientCertificate();
+  asyncStart();
+  testClientCertificate()
+    .then((_) => testRequiredClientCertificate())
+    .then((_) => asyncEnd());
 }