Updating Polymer to derive from custom elements.

pkg/polymer/test/publish_attributes_test.dart

 // Copyright (c) 2013, 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.
 
 import 'dart:html';
 import 'package:unittest/unittest.dart';
 import 'package:unittest/html_config.dart';
 import 'package:polymer/polymer.dart';
 
 // Dart note: unlike JS, you can't publish something that doesn't
 // have a corresponding field because we can't dynamically add properties.
 // So we define XFoo and XBar types here.
 @CustomTag('x-foo')
 class XFoo extends PolymerElement {
+  XFoo.created() : super.created();
+
   @observable var Foo;
   @observable var baz;
 }
 
 @CustomTag('x-bar')
 class XBar extends XFoo {
+  XBar.created() : super.created();
+
   @observable var Bar;
 }
 
 @CustomTag('x-zot')
 class XZot extends XBar {
+  XZot.created() : super.created();
+
   @published int zot = 3;
 }
 
 @CustomTag('x-squid')
 class XSquid extends XZot {
+  XSquid.created() : super.created();
+
   @published int baz = 13;
   @published int zot = 5;
   @published int squid = 7;
 }
 
 main() {
   useHtmlConfiguration();
 
   test('published properties', () {
     published(tag) =>
         query('polymer-element[name=$tag]').xtag.publishedProperties;
 
     print(published('x-foo'));
     print(published('x-bar'));
     print(published('x-zot'));
     print(published('x-squid'));
 
     expect(published('x-foo'), ['Foo', 'baz']);
     expect(published('x-bar'), ['Foo', 'baz', 'Bar']);
     expect(published('x-zot'), ['Foo', 'baz', 'Bar', 'zot']);
     expect(published('x-squid'), ['Foo', 'baz', 'Bar', 'zot', 'squid']);
   });
 }