Change dart2js_foreign suite to use metadata.

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 a21ff2ebfb9b31b848cbfa397bf91ee36ca2ef71..2182e855f252e26e1224b3635507624780966f3b 100644
--- a/dart/tests/compiler/dart2js_foreign/native_to_string_test.dart
+++ b/dart/tests/compiler/dart2js_foreign/native_to_string_test.dart
@@ -2,13 +2,15 @@
 // 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 A native "*A" {}
-makeA() native;
+@native("*A")
+class A  {}
+@native makeA();
 
-void setup() native """
+@native("""
 function A() {}
 makeA = function(){return new A;};
-""";
+""")
+void setup();
 
 
 main() {