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

sdk/lib/_internal/pub_generated/test/dart2js/source_maps_include_core_libs_in_subdirectory_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.
 
 import 'package:path/path.dart' as path;
 import 'package:scheduled_test/scheduled_test.dart';
 
 import '../descriptor.dart' as d;
 import '../serve/utils.dart';
 import '../test_pub.dart';
 
 main() {
   initConfig();
 
   // This test is a bit shaky. Since dart2js is free to inline things, it's
   // not precise as to which source libraries will actually be referenced in
   // the source map. But this tries to use a type in the core library
   // (StringBuffer) and validate that its source ends up in the source map.
-  integration("Dart core libraries are available to source maps when the "
-      "build directory is a subdirectory", () {
-    d.dir(appPath, [
-      d.appPubspec(),
-      d.dir("web", [
-        d.dir("sub", [
-          d.file("main.dart", "main() => new StringBuffer().writeAll(['s']);")
-        ])
-      ])
-    ]).create();
+  integration(
+      "Dart core libraries are available to source maps when the "
+          "build directory is a subdirectory",
+      () {
+    d.dir(
+        appPath,
+        [
+            d.appPubspec(),
+            d.dir(
+                "web",
+                [
+                    d.dir(
+                        "sub",
+                        [
+                            d.file(
+                                "main.dart",
+                                "main() => new StringBuffer().writeAll(['s']);")])])]).create();
 
     var webSub = path.join("web", "sub");
     pubServe(args: [webSub]);
 
-    requestShouldSucceed("main.dart.js.map",
+    requestShouldSucceed(
+        "main.dart.js.map",
         contains(r"packages/$sdk/lib/core/string_buffer.dart"),
         root: webSub);
-    requestShouldSucceed(r"packages/$sdk/lib/core/string_buffer.dart",
+    requestShouldSucceed(
+        r"packages/$sdk/lib/core/string_buffer.dart",
         contains("class StringBuffer"),
         root: webSub);
 
     endPubServe();
   });
 }