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

sdk/lib/_internal/pub_generated/test/get/hosted/stay_locked_if_compatible_test.dart

 // Copyright (c) 2012, 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.
 
 library pub_tests;
 
 import '../../descriptor.dart' as d;
 import '../../test_pub.dart';
 
 main() {
   initConfig();
-  integration("doesn't upgrade a locked pub server package with a new "
-      "compatible constraint", () {
+  integration(
+      "doesn't upgrade a locked pub server package with a new "
+          "compatible constraint",
+      () {
     servePackages((builder) => builder.serve("foo", "1.0.0"));
 
-    d.appDir({"foo": "any"}).create();
+    d.appDir({
+      "foo": "any"
+    }).create();
 
     pubGet();
 
-    d.packagesDir({"foo": "1.0.0"}).validate();
+    d.packagesDir({
+      "foo": "1.0.0"
+    }).validate();
 
     servePackages((builder) => builder.serve("foo", "1.0.1"));
 
-    d.appDir({"foo": ">=1.0.0"}).create();
+    d.appDir({
+      "foo": ">=1.0.0"
+    }).create();
 
     pubGet();
 
-    d.packagesDir({"foo": "1.0.0"}).validate();
+    d.packagesDir({
+      "foo": "1.0.0"
+    }).validate();
   });
 }