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

tests/compiler/dart2js_native/native_field_invocation2_test.dart

Index: tests/compiler/dart2js_native/native_field_invocation2_test.dart
diff --git a/tests/compiler/dart2js_native/native_field_invocation2_test.dart b/tests/compiler/dart2js_native/native_field_invocation2_test.dart
index 29c261cca2f3f990c666a637fcaf118208748856..7b6dc9084d22be71c16b33ae9239c7fdcd320788 100644
--- a/tests/compiler/dart2js_native/native_field_invocation2_test.dart
+++ b/tests/compiler/dart2js_native/native_field_invocation2_test.dart
@@ -2,9 +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.
 
+import "dart:_js_helper";
 import "package:expect/expect.dart";
 
-class NNative native "NNative" {
+@Native("NNative")
+class NNative {
   var status;
 
   var f;