Revert "Revert "Use native async/await support in pub.""

sdk/lib/_internal/pub_generated/test/lish/preview_errors_if_private_test.dart

Index: sdk/lib/_internal/pub_generated/test/lish/preview_errors_if_private_test.dart
diff --git a/sdk/lib/_internal/pub_generated/test/lish/preview_errors_if_private_test.dart b/sdk/lib/_internal/pub_generated/test/lish/preview_errors_if_private_test.dart
deleted file mode 100644
index 642c5c39d65adb95fe9ce40139cc066e5a1926d7..0000000000000000000000000000000000000000
--- a/sdk/lib/_internal/pub_generated/test/lish/preview_errors_if_private_test.dart
+++ /dev/null
@@ -1,23 +0,0 @@
-// 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.
-
-import 'package:scheduled_test/scheduled_test.dart';
-
-import '../../lib/src/exit_codes.dart' as exit_codes;
-import '../descriptor.dart' as d;
-import '../test_pub.dart';
-
-main() {
-  initConfig();
-  integration('preview shows an error if the package is private', () {
-    var pkg = packageMap("test_pkg", "1.0.0");
-    pkg["publish_to"] = "none";
-    d.dir(appPath, [d.pubspec(pkg)]).create();
-
-    schedulePub(
-        args: ["lish", "--dry-run"],
-        error: startsWith("A private package cannot be published."),
-        exitCode: exit_codes.DATA);
-  });
-}