Regenerate pub sources.

sdk/lib/_internal/pub_generated/test/list_package_dirs/missing_pubspec_test.dart

Index: sdk/lib/_internal/pub_generated/test/list_package_dirs/missing_pubspec_test.dart
diff --git a/sdk/lib/_internal/pub_generated/test/list_package_dirs/missing_pubspec_test.dart b/sdk/lib/_internal/pub_generated/test/list_package_dirs/missing_pubspec_test.dart
index 3503a8d5cca237a63badfe023f9114ab64a944f1..0838cd2171b6585f37eedbc7ea5f76033baf3d43 100644
--- a/sdk/lib/_internal/pub_generated/test/list_package_dirs/missing_pubspec_test.dart
+++ b/sdk/lib/_internal/pub_generated/test/list_package_dirs/missing_pubspec_test.dart
@@ -1,11 +1,19 @@
+// 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 d.file.
+
 import 'package:path/path.dart' as path;
+
 import '../../lib/src/io.dart';
 import '../descriptor.dart' as d;
 import '../test_pub.dart';
+
 main() {
   initConfig();
+  // This is a regression test for #20065.
   integration("reports a missing pubspec error using JSON", () {
     d.dir(appPath).create();
+
     schedulePub(args: ["list-package-dirs", "--format=json"], outputJson: {
       "error": 'Could not find a file named "pubspec.yaml" in "'
           '${canonicalize(path.join(sandboxDir, appPath))}".',