Add mirrors tests

test/codegen/lib/mirrors/closure_mirror_import2.dart

 // Copyright (c) 2013, 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 file.
 
-class BootstrapTest {
+library closure_mirror_import2;
 
-  static testMain() {
-    var obj = new Object();
-
-    return obj;
-  }
-
-}
-
-main() {
-  BootstrapTest.testMain();
-}
+var firstGlobalVariableInImport2 = "firstGlobalVariableInImport2";
+var secondGlobalVariableInImport2 = "secondGlobalVariableInImport2";