Add property base to the Uri class

tests/html/uri_test.dart

Index: tests/html/uri_test.dart
diff --git a/tests/html/mouse_event_test.dart b/tests/html/uri_test.dart
similarity index 60%
copy from tests/html/mouse_event_test.dart
copy to tests/html/uri_test.dart
index 4be967bda1b0d60fb55b220d9231f8480fa70328..af2ae82bbc5c7c2a850919540f057dba3bedc4c9 100644
--- a/tests/html/mouse_event_test.dart
+++ b/tests/html/uri_test.dart
@@ -1,8 +1,7 @@
-// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
+// 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 mouse_event_test;
 import '../../pkg/unittest/lib/unittest.dart';
 import '../../pkg/unittest/lib/html_config.dart';
 import 'dart:html';
@@ -10,8 +9,8 @@ import 'dart:html';
 main() {
   useHtmlConfiguration();
 
-  test('relatedTarget', () {
-    var event = new MouseEvent('mouseout');
-    expect(event.relatedTarget, isNull);
+  test('Uri.base', () {
+    expect(Uri.base.scheme, "http");
+    expect(Uri.base.toString(), window.location.href);
   });
 }