Migrate block 163 to Dart 2.0.

tests/language_2/unresolved_top_level_var_test.dart

Index: tests/language_2/unresolved_top_level_var_test.dart
diff --git a/tests/language/unresolved_top_level_var_negative_test.dart b/tests/language_2/unresolved_top_level_var_test.dart
similarity index 64%
rename from tests/language/unresolved_top_level_var_negative_test.dart
rename to tests/language_2/unresolved_top_level_var_test.dart
index 589ddd5e6c1ddabf5de17631a9c54849d83a78b1..daf5305017ca3cd0d4ebc5ed04eafd957a9f2eb2 100644
--- a/tests/language/unresolved_top_level_var_negative_test.dart
+++ b/tests/language_2/unresolved_top_level_var_test.dart
@@ -2,11 +2,11 @@
 // 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.
 
-// Test that an unresolved identifier at the top level does not crash
-// the parser.
+// Test that an unresolved identifier at the top level causes a compile-time
+// error.
 
-var a = b;
+var a = b; /*@compile-error=unspecified*/
 
 main() {
   print(a);
-}
+}