Start pulling pub from its own repo.

sdk/lib/_internal/pub/test/cache/repair/handles_corrupted_global_lockfile_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.
-
-library pub_tests;
-
-import 'package:scheduled_test/scheduled_test.dart';
-
-import '../../descriptor.dart' as d;
-import '../../test_pub.dart';
-
-main() {
-  initConfig();
-  integration('handles a corrupted global lockfile', () {
-    d.dir(cachePath, [
-      d.dir('global_packages/foo', [
-        d.file('pubspec.lock', 'junk')
-      ])
-    ]).create();
-
-    schedulePub(args: ["cache", "repair"],
-        error: contains('Failed to reactivate foo:'),
-        output: contains('Failed to reactivate 1 package.'));
-  });
-}