Use native async/await support in pub.

sdk/lib/_internal/pub_generated/test/cache/repair/handles_failure_test.dart

-// Copyright (c) 2014, 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 'package:scheduled_test/scheduled_test.dart';
-
-import '../../../lib/src/exit_codes.dart' as exit_codes;
-import '../../descriptor.dart' as d;
-import '../../test_pub.dart';
-
-main() {
-  initConfig();
-  integration('handles failure to reinstall some packages', () {
-    // Only serve two packages so repairing will have a failure.
-    servePackages((builder) {
-      builder.serve("foo", "1.2.3");
-      builder.serve("foo", "1.2.5");
-    });
-
-    // Set up a cache with some packages.
-    d.dir(
-        cachePath,
-        [
-            d.dir(
-                'hosted',
-                [
-                    d.async(
-                        port.then(
-                            (p) =>
-                                d.dir(
-                                    'localhost%58$p',
-                                    [
-                                        d.dir("foo-1.2.3", [d.libPubspec("foo", "1.2.3"), d.file("broken.txt")]),
-                                        d.dir("foo-1.2.4", [d.libPubspec("foo", "1.2.4"), d.file("broken.txt")]),
-                                        d.dir(
-                                            "foo-1.2.5",
-                                            [d.libPubspec("foo", "1.2.5"), d.file("broken.txt")])])))])]).create();
-
-    // Repair them.
-    var pub = startPub(args: ["cache", "repair"]);
-
-    pub.stdout.expect("Downloading foo 1.2.3...");
-    pub.stdout.expect("Downloading foo 1.2.4...");
-    pub.stdout.expect("Downloading foo 1.2.5...");
-
-    pub.stderr.expect(startsWith("Failed to repair foo 1.2.4. Error:"));
-    pub.stderr.expect("HTTP error 404: Not Found");
-
-    pub.stdout.expect("Reinstalled 2 packages.");
-    pub.stdout.expect("Failed to reinstall 1 package.");
-
-    pub.shouldExit(exit_codes.UNAVAILABLE);
-  });
-}