Update dart2js_foreign suite as we now validate annotations.

dart/tests/compiler/dart2js_foreign/native_to_string_test.dart

Index: dart/tests/compiler/dart2js_foreign/native_to_string_test.dart
diff --git a/dart/tests/compiler/dart2js_foreign/native_to_string_test.dart b/dart/tests/compiler/dart2js_foreign/native_to_string_test.dart
index 87059b91d56eea472c5b04b2a6fdf6befc46111c..959b2ca5f5210e2b7dae5a24d792d815ef790167 100644
--- a/dart/tests/compiler/dart2js_foreign/native_to_string_test.dart
+++ b/dart/tests/compiler/dart2js_foreign/native_to_string_test.dart
@@ -2,11 +2,13 @@
 // 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.
 
-@native("*A")
+import 'native_metadata.dart';
+
+@Native("*A")
 class A {}
 @native makeA();
 
-@native("""
+@Native("""
 function A() {}
 makeA = function(){return new A;};
 """)