update elements and fix some bugs

test/iron_icon_test.dart

 // Copyright (c) 2015, 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.
 @TestOn('browser')
 library polymer_elements.test.iron_icon_test;
 
 import 'dart:html';
 import 'dart:js';
 import 'package:polymer_elements/iron_icon.dart';
 import 'package:polymer_elements/iron_iconset.dart';
@@ skipping 51 matching lines @@
 
       test('can change its icon dynamically', () {
         var style = icon.style;
         expect(
             style.backgroundPosition, contains(new RegExp(r'0(%|px) 0(%|px)')));
         icon.icon = "example:blank";
         expect(
             style.backgroundPosition, contains(new RegExp(r'-24px 0(%|px)')));
       });
     });
+
     group('when no icon source is provided', () {
       test('will politely wait for an icon source without throwing', () {
         document.createElement('iron-icon');
         fixture('WithoutAnIconSource');
       });
     });
+
+    group('when loading async', () {
+      test('will get icon after iconset is added', () {
+        var icon = fixture('UsingAsyncIconset');
+        expect(hasIcon(icon), isFalse);
+
+        var done = window.on['iron-iconset-added'].first.then((_) {
+          expect(hasIcon(icon), isTrue,
+              reason: 'icon didn\'t load after iconset loaded');
+        });
+        fixture('AsyncIconset');
+
+        return done;
+      });
+    });
   });
 }