Fix http test

tests/compiler/dart2js/quarantined/http_test.dart

 // Copyright (c) 2014, 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.
 //
 // Test:
 //   *) Compiling a script fetched over HTTP.
 //   *) Importing a library fetched over HTTP.
 //   *) Automatically resolving package_root when script is fetched over HTTP.
 
 library http_launch_test;
 
 import 'dart:async';
 import 'dart:io';
 import 'package:async_helper/async_helper.dart';
 import 'package:expect/expect.dart';
 import 'package:path/path.dart' as path;
 
-Uri pathOfData = Platform.script.resolve('../http_launch_data/');
+import '../launch_helper.dart' show launchDart2Js;
+
+Uri pathOfData = Platform.script.resolve('http_launch_data/');
 Directory tempDir;
 String outFilePath;
 
 _sendNotFound(HttpResponse response) {
   response.statusCode = HttpStatus.NOT_FOUND;
   response.close();
 }
 
 Future handleRequest(HttpRequest request) {
   final String path = request.uri.path.substring(1);
   final Uri requestPath = pathOfData.resolve(path);
   final File file = new File(requestPath.toFilePath());
   return file.exists().then((bool found) {
     if (found) {
       file.openRead()
           .pipe(request.response)
           .catchError((e) { _sendNotFound(request.response); });
     } else {
       _sendNotFound(request.response);
     }
   });
 }
 
-Future launchDart2Js(args) {
-  String ext = Platform.isWindows ? '.bat' : '';
-  String command =
-      path.normalize(path.join(path.fromUri(Platform.script),
-                    '../../../../../sdk/bin/dart2js${ext}'));
-  return Process.run(command, args);
-}
-
 void check(ProcessResult result) {
   Expect.equals(0, result.exitCode);
   File outFile = new File(outFilePath);
   Expect.isTrue(outFile.existsSync());
   Expect.isTrue(outFile.readAsStringSync().contains("hello http tester"));
 }
 
 void checkNotFound(ProcessResult result, String filename) {
   Expect.notEquals(0, result.exitCode);
   File outFile = new File(outFilePath);
@@ skipping 112 matching lines @@
                                certificateName: 'localhost_cert')
       .then((HttpServer server) => serverRunning(server, "https"));
 }
 
 main() {
   asyncStart();
   testHttp()
     .then((_) => testHttps)
     .whenComplete(asyncEnd);
 }