Add mirrors tests

test/codegen/lib/mirrors/empty.dart

Index: test/codegen/lib/mirrors/empty.dart
diff --git a/test/codegen/language/getter_setter_in_lib2.dart b/test/codegen/lib/mirrors/empty.dart
similarity index 81%
copy from test/codegen/language/getter_setter_in_lib2.dart
copy to test/codegen/lib/mirrors/empty.dart
index addfb650fcbe8db0056d793caa6fe2fe5ece85fe..ee5f193a03cbc33674b250f5a6e5eca3c1566d5b 100644
--- a/test/codegen/language/getter_setter_in_lib2.dart
+++ b/test/codegen/lib/mirrors/empty.dart
@@ -2,6 +2,5 @@
 // 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 GetterSetterInLib2;
-
-set bar(a) { }
+// This library has no functions.
+library empty;