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

sdk/lib/_internal/pub_generated/test/validator/utf8_readme_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/utf8_readme.dart';
 import '../descriptor.dart' as d;
 import '../test_pub.dart';
 import 'utils.dart';
 
 Validator utf8Readme(Entrypoint entrypoint) =>
-  new Utf8ReadmeValidator(entrypoint);
+    new Utf8ReadmeValidator(entrypoint);
 
 main() {
   initConfig();
 
   group('should consider a package valid if it', () {
     setUp(d.validPackage.create);
 
     integration('looks normal', () => expectNoValidationError(utf8Readme));
 
     integration('has a non-primary readme with invalid utf-8', () {
-      d.dir(appPath, [
-        d.file("README", "Valid utf-8"),
-        d.binaryFile("README.invalid", [192])
-      ]).create();
+      d.dir(
+          appPath,
+          [
+              d.file("README", "Valid utf-8"),
+              d.binaryFile("README.invalid", [192])]).create();
       expectNoValidationError(utf8Readme);
     });
   });
 
-  integration('should consider a package invalid if it has a README with '
-      'invalid utf-8', () {
+  integration(
+      'should consider a package invalid if it has a README with ' 'invalid utf-8',
+      () {
     d.validPackage.create();
 
-    d.dir(appPath, [
-      d.binaryFile("README", [192])
-    ]).create();
+    d.dir(appPath, [d.binaryFile("README", [192])]).create();
     expectValidationWarning(utf8Readme);
   });
 }