test rename overhaul: step 8 - language tests

tests/language/disable_privacy_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.
 // VMOptions=--disable_privacy
 //
 // Dart test program checking that library privacy can be disabled.
 
 #library('DisablePrivacyTest');
-#import("DisablePrivacyLib.dart");
+#import("disable_privacy_lib.dart");
 
 main() {
   Expect.equals(1, _fooForTesting);
 }