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

sdk/lib/_internal/pub_generated/test/validator/executable_test.dart

-// Copyright (c) 2013, 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/entrypoint.dart';
-import '../../lib/src/validator.dart';
-import '../../lib/src/validator/executable.dart';
-import '../descriptor.dart' as d;
-import '../test_pub.dart';
-import 'utils.dart';
-
-Validator executable(Entrypoint entrypoint) =>
-    new ExecutableValidator(entrypoint);
-
-main() {
-  initConfig();
-
-  setUp(d.validPackage.create);
-
-  group('should consider a package valid if it', () {
-    integration('has executables that are present', () {
-      d.dir(appPath, [d.pubspec({
-          "name": "test_pkg",
-          "version": "1.0.0",
-          "executables": {
-            "one": "one_script",
-            "two": null
-          }
-        }),
-            d.dir(
-                "bin",
-                [
-                    d.file("one_script.dart", "main() => print('ok');"),
-                    d.file("two.dart", "main() => print('ok');")])]).create();
-      expectNoValidationError(executable);
-    });
-  });
-
-  group("should consider a package invalid if it", () {
-    integration('is missing one or more listed executables', () {
-      d.dir(appPath, [d.pubspec({
-          "name": "test_pkg",
-          "version": "1.0.0",
-          "executables": {
-            "nope": "not_there",
-            "nada": null
-          }
-        })]).create();
-      expectValidationWarning(executable);
-    });
-  });
-}