Update unittest to new package layout.

tests/html/form_data_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.
 
 #library('FormDataTest');
 
-#import('../../pkg/unittest/unittest.dart');
-#import('../../pkg/unittest/html_config.dart');
+#import('../../pkg/unittest/lib/unittest.dart');
+#import('../../pkg/unittest/lib/html_config.dart');
 #import('dart:html');
 
 void main() {
   // TODO(efortuna): This is a bad test. Revisit when we have tests that can run
   // both a server and fire up a browser.
   useHtmlConfiguration();
 
   test('constructorTest1', () {
     var form = new FormData();
     expect(form, isNotNull);
     expect(form is FormData);
   });
 
   test('constructorTest2', () {
     var form = new FormData(new FormElement());
     expect(form, isNotNull);
     expect(form is FormData);
   });
 
   test('appendTest', () {
     var form = new FormData();
     form.append('test', '1', 'foo');
     form.append('username', 'Elmo', 'foo');
     form.append('address', '1 Sesame Street', 'foo');
     form.append('password', '123456', 'foo');
     expect(form, isNotNull);
   });
 }