Use native async/await support in pub.

sdk/lib/_internal/pub_generated/test/dart2js/does_not_compile_if_disabled_test.dart

Index: sdk/lib/_internal/pub_generated/test/dart2js/does_not_compile_if_disabled_test.dart
diff --git a/sdk/lib/_internal/pub_generated/test/dart2js/does_not_compile_if_disabled_test.dart b/sdk/lib/_internal/pub_generated/test/dart2js/does_not_compile_if_disabled_test.dart
deleted file mode 100644
index 6de1fdc1e02601f8c29f031b6146c42dec7d3438..0000000000000000000000000000000000000000
--- a/sdk/lib/_internal/pub_generated/test/dart2js/does_not_compile_if_disabled_test.dart
+++ /dev/null
@@ -1,24 +0,0 @@
-// 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 '../descriptor.dart' as d;
-import '../test_pub.dart';
-import '../serve/utils.dart';
-
-main() {
-  initConfig();
-  integration("does not compile if dart2js is disabled", () {
-    d.dir(
-        appPath,
-        [
-            d.appPubspec(),
-            d.dir(
-                "web",
-                [d.file("main.dart", "void main() => print('hello');")])]).create();
-
-    pubServe(args: ["--no-dart2js"]);
-    requestShould404("main.dart.js");
-    endPubServe();
-  });
-}