Revert "First step for modular output in fasta."

pkg/front_end/testcases/shaker/toplevel_reference.dart

Index: pkg/front_end/testcases/shaker/toplevel_reference.dart
diff --git a/pkg/front_end/testcases/shaker/toplevel_reference.dart b/pkg/front_end/testcases/shaker/toplevel_reference.dart
deleted file mode 100644
index 12f211121509fa9d4dfd401bfe899dbd5e2ebe2f..0000000000000000000000000000000000000000
--- a/pkg/front_end/testcases/shaker/toplevel_reference.dart
+++ /dev/null
@@ -1,8 +0,0 @@
-// Copyright (c) 2017, 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.md file.
-
-import 'lib/lib.dart';
-
-/// Direct references to toplevel members are preserved
-main() => toplevel();