Start pulling pub from its own repo.

sdk/lib/_internal/pub/test/transformer/a_transformer_rejects_its_config_test.dart

-// Copyright (c) 2014, 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 'package:scheduled_test/scheduled_test.dart';
-
-import '../descriptor.dart' as d;
-import '../test_pub.dart';
-import '../serve/utils.dart';
-
-const REJECT_CONFIG_TRANSFORMER = """
-import 'dart:async';
-
-import 'package:barback/barback.dart';
-
-class RejectConfigTransformer extends Transformer {
-  RejectConfigTransformer.asPlugin(BarbackSettings settings) {
-    throw "I hate these settings!";
-  }
-
-  Future<bool> isPrimary(_) => new Future.value(true);
-  Future apply(Transform transform) {}
-}
-""";
-
-main() {
-  initConfig();
-
-  withBarbackVersions("any", () {
-     integration("a transformer can reject is configuration", () {
-       d.dir(appPath, [
-         d.pubspec({
-           "name": "myapp",
-           "transformers": [{"myapp/src/transformer": {'foo': 'bar'}}]
-         }),
-         d.dir("lib", [d.dir("src", [
-           d.file("transformer.dart", REJECT_CONFIG_TRANSFORMER)
-         ])])
-       ]).create();
-
-       createLockFile('myapp', pkg: ['barback']);
-
-       var pub = startPubServe();
-       pub.stderr.expect(endsWith('Error loading transformer: I hate these '
-           'settings!'));
-       pub.shouldExit(1);
-     });
-  });
-}