Add @Native(...) annotation for native class names.

tests/compiler/dart2js_native/uninstantiated_type_parameter_test.dart

Index: tests/compiler/dart2js_native/uninstantiated_type_parameter_test.dart
diff --git a/tests/compiler/dart2js_native/uninstantiated_type_parameter_test.dart b/tests/compiler/dart2js_native/uninstantiated_type_parameter_test.dart
index 61f3b604b95594b70bff6e1af57327cd5e7f2b21..43efdb6c8e9623438337c5c9fc536c7915b65a9b 100644
--- a/tests/compiler/dart2js_native/uninstantiated_type_parameter_test.dart
+++ b/tests/compiler/dart2js_native/uninstantiated_type_parameter_test.dart
@@ -2,6 +2,7 @@
 // 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.
 
+import "dart:_js_helper";
 import "package:expect/expect.dart";
 
 // Test for uninstantiated native classes as type parameters.
@@ -9,7 +10,8 @@ import "package:expect/expect.dart";
 class UA {
 }
 
-class UB native "B" {
+@Native("B")
+class UB {
 }
 
 class C<T> {