Update unittest to new package layout.

tests/html/element_test.dart

 // Copyright (c) 2011, 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('ElementTest');
-#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');
 
 expectLargeRect(ClientRect rect) {
   Expect.equals(rect.top, 0);
   Expect.equals(rect.left, 0);
   Expect.isTrue(rect.width > 100);
   Expect.isTrue(rect.height > 100);
   Expect.equals(rect.bottom, rect.top + rect.height);
   Expect.equals(rect.right, rect.left + rect.width);
 }
@@ skipping 725 matching lines @@
     });
 
     test('getRange', () {
       var range = makeElList().getRange(1, 2);
       Expect.isTrue(range is ElementList);
       Expect.isTrue(range[0] is ImageElement);
       Expect.isTrue(range[1] is InputElement);
     });
   });
 }