Use the new test runner.

test/build/defaults_to_release_mode_test.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS d.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.
 
 library pub_tests;
 
 import '../descriptor.dart' as d;
 import '../test_pub.dart';
 
 const TRANSFORMER = """
@@ skipping 10 matching lines @@
   Future apply(Transform transform) {
     return new Future.value().then((_) {
       var id = transform.primaryInput.id.changeExtension(".out");
       transform.addOutput(new Asset.fromString(id, settings.mode.toString()));
     });
   }
 }
 """;
 
 main() {
-  initConfig();
   withBarbackVersions("any", () {
     integration("defaults to release mode", () {
       d.dir(appPath, [
         d.pubspec({
           "name": "myapp",
           "transformers": ["myapp/src/transformer"]
         }),
         d.dir("lib", [d.dir("src", [
           d.file("transformer.dart", TRANSFORMER)
         ])]),
         d.dir("web", [
           d.file("foo.txt", "foo")
         ])
       ]).create();
 
       createLockFile('myapp', pkg: ['barback']);
 
       schedulePub(args: ["build"]);
 
       d.dir(appPath, [
         d.dir('build', [
           d.dir('web', [
             d.file('foo.out', 'release')
           ])
         ])
       ]).validate();
     });
   });
 }