Move unittest from lib to pkg.

tests/html/xmldocument_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('XMLDocumentTest');
-#import('../../lib/unittest/unittest.dart');
-#import('../../lib/unittest/html_config.dart');
+#import('../../pkg/unittest/unittest.dart');
+#import('../../pkg/unittest/html_config.dart');
 #import('dart:html');
 
 main() {
   useHtmlConfiguration();
 
   XMLDocument makeDocument() => new XMLDocument.xml("<xml><foo/><bar/></xml>");
 
   group('constructor', () {
     test('with a well-formed document', () {
       final doc = makeDocument();
@@ skipping 593 matching lines @@
     test('manifest', () => Expect.equals('', makeDocument().manifest));
   });
 
   test('unsupported operations', () {
     expectUnsupported(() { makeDocument().body = new XMLElement.tag('xml'); });
     expectUnsupported(() => makeDocument().cookie);
     expectUnsupported(() { makeDocument().cookie = 'foo'; });
     expectUnsupported(() { makeDocument().manifest = 'foo'; });
   });
 }