Rollback instrumentation during analysis and validate resolved ASTs instead.

pkg/front_end/testcases/inference/toplevel_inference_toplevel_var.dart

Index: pkg/front_end/testcases/inference/toplevel_inference_toplevel_var.dart
diff --git a/pkg/front_end/testcases/inference/toplevel_inference_toplevel_var.dart b/pkg/front_end/testcases/inference/toplevel_inference_toplevel_var.dart
index fc9970c9aa92b0160d4009224286aa3ff798f74e..86a6ea3841e7965006311eb533748eaa820cad64 100644
--- a/pkg/front_end/testcases/inference/toplevel_inference_toplevel_var.dart
+++ b/pkg/front_end/testcases/inference/toplevel_inference_toplevel_var.dart
@@ -1,4 +1,10 @@
+// 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.
+
 /*@testedFeatures=inference*/
+library test;
+
 var /*@topType=int*/ i = 0;
 
 main() {