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

sdk/lib/_internal/pub_generated/test/transformer/fails_to_load_a_transform_with_an_import_error_test.dart

 // Copyright (c) 2013, 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';
 
 main() {
   initConfig();
 
   // An import error will cause the isolate API to fail synchronously while
   // loading the transformer.
   withBarbackVersions("any", () {
     integration("fails to load a transform with an import error", () {
-      d.dir(appPath, [
-        d.pubspec({
+      d.dir(appPath, [d.pubspec({
           "name": "myapp",
           "transformers": ["myapp/src/transformer"]
         }),
-        d.dir("lib", [d.dir("src", [
-          d.file("transformer.dart", "import 'does/not/exist.dart';")
-        ])])
-      ]).create();
+            d.dir(
+                "lib",
+                [
+                    d.dir(
+                        "src",
+                        [d.file("transformer.dart", "import 'does/not/exist.dart';")])])]).create();
 
       createLockFile('myapp', pkg: ['barback']);
       var pub = startPubServe();
       pub.stderr.expect("Unhandled exception:");
       pub.stderr.expect(
           startsWith("Uncaught Error: Load Error: Failure getting "));
       pub.shouldExit(1);
     });
   });
 }