Add redirect support to the HTTP client

tests/standalone/io/http_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
 // VMOptions=--short_socket_write
 // VMOptions=--short_socket_read --short_socket_write
 
 #import("dart:isolate");
@@ skipping 413 matching lines @@
   testServerMain.start();
 }
 
 
 void testReasonPhrase() {
   TestServerMain testServerMain = new TestServerMain();
   testServerMain.setServerStartedHandler((int port) {
     HttpClient httpClient = new HttpClient();
     HttpClientConnection conn =
         httpClient.get("127.0.0.1", port, "/reasonformoving");
+    conn.followRedirects = false;
     conn.onResponse = (HttpClientResponse response) {
       Expect.equals(HttpStatus.MOVED_PERMANENTLY, response.statusCode);
       Expect.equals("Don't come looking here any more", response.reasonPhrase);
       httpClient.shutdown();
       testServerMain.shutdown();
     };
   });
   testServerMain.start();
 }
 
@@ skipping 77 matching lines @@
   testPOST(false);
   testReadInto(true);
   testReadInto(false);
   testReadShort(true);
   testReadShort(false);
   test404();
   testReasonPhrase();
   testHost();
   testExpires();
 }