Fix typo in test.

tests/language/metadata_test.dart

 // Copyright (c) 2012, 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.
 
 // Test ensuring that compiler can parse metadata. Need to add negative
 // test cases with illegal metadata annotations.
 
 library metadata_test.dart;
 
 import "package:expect/expect.dart";
 import "metadata_lib.dart" as Meta;
 
 class Tag {
   final String annotation;
   const Tag(this.annotation);
 }
 
 const meta1 = 1;
 const meta2 = const Tag("meta2");
 
 const extern = const Tag("external");
 
 @meta1
 var topLevelVar;
-@Meta.Alien.unspecified()
+@Meta.Alien.unknown()
 List unknownUnknowns;
 
 @meta1
 typedef int DingDong<@meta2 T>(@meta1 event);
 
 @meta1
 class A<@Tag("typeParam") T> {
   @meta1
   @meta2
   static String staticField;
@@ skipping 17 matching lines @@
   for (@Tag("loopvar")
   int i = 0;
       i < 10;
       i++) {
     // Do something.
   }
 
   @meta1
   var s = r'This is a raw \\ string.';
 }