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

sdk/lib/_internal/pub_generated/test/serve/serve_from_app_lib_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 '../descriptor.dart' as d;
 import '../test_pub.dart';
 import 'utils.dart';
 
 main() {
   initConfig();
   integration("'packages' URLs look in the app's lib directory", () {
-    d.dir(appPath, [
-      d.appPubspec(),
-      d.dir("lib", [
-        d.file("lib.dart", "foo() => 'foo';"),
-        d.dir("sub", [
-          d.file("lib.dart", "bar() => 'bar';"),
-        ])
-      ])
-    ]).create();
+    d.dir(
+        appPath,
+        [
+            d.appPubspec(),
+            d.dir(
+                "lib",
+                [
+                    d.file("lib.dart", "foo() => 'foo';"),
+                    d.dir("sub", [d.file("lib.dart", "bar() => 'bar';"),])])]).create();
 
     pubServe();
     requestShouldSucceed("packages/myapp/lib.dart", "foo() => 'foo';");
     requestShouldSucceed("packages/myapp/sub/lib.dart", "bar() => 'bar';");
 
     // "packages" can be in a subpath of the URL:
     requestShouldSucceed("foo/packages/myapp/lib.dart", "foo() => 'foo';");
     requestShouldSucceed("a/b/packages/myapp/sub/lib.dart", "bar() => 'bar';");
     endPubServe();
   });
 }