Fix errors in dart:io tests found by the analyzer

tests/standalone/io/raw_secure_server_socket_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 "dart:async";
@@ skipping 35 matching lines @@
     Expect.isTrue(error is SocketException);
     asyncEnd();
   });
 
   // Bind to a port already in use.
   asyncStart();
   RawSecureServerSocket.bind(HOST_NAME, 0, CERTIFICATE).then((s) {
     RawSecureServerSocket.bind(HOST_NAME,
                                s.port,
                                CERTIFICATE).then((t) {
-      Expect.fail("Multiple listens on same port");
       s.close();
       t.close();
-      port.toSendPort().send(1);
+      Expect.fail("Multiple listens on same port");
     })
     .catchError((error) {
       Expect.isTrue(error is SocketException);
       s.close();
-    asyncEnd();
+      asyncEnd();
     });
   });
 }
 
 void testSimpleConnect(String certificate) {
   asyncStart();
   RawSecureServerSocket.bind(HOST_NAME, 0, certificate).then((server) {
     var clientEndFuture = RawSecureSocket.connect(HOST_NAME, server.port);
     server.listen((serverEnd) {
       clientEndFuture.then((clientEnd) {
@@ skipping 446 matching lines @@
                       connectSecure: true,
                       handshakeBeforeSecure: false,
                       postponeSecure: false,
                       dropReads: true);
   testSimpleReadWrite(listenSecure: false,
                       connectSecure: false,
                       handshakeBeforeSecure: true,
                       postponeSecure: true,
                       dropReads: true);
 }