Update TodoMVC based on https://github.com/polymer/todomvc

samples/third_party/todomvc/web/editable_label.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.
-
-library todomvc.web.editable_label;
-
-import 'dart:html';
-import 'package:polymer/polymer.dart';
-
-/**
- * Label whose [value] can be edited by double clicking. When editing, it
- * displays a form and input element, otherwise it displays the label.
- */
-// For illustration purposes this type uses Polymer.register instead of
-// CustomTag. We must mark it @reflectable to ensure its members
-// (the event handlers) are preserved and can be referenced from HTML.
-@reflectable
-class EditableLabel extends PolymerElement {
-  @observable bool editing = false;
-  @published String value = '';
-
-  factory EditableLabel() => new Element.tag('editable-label');
-
-  EditableLabel.created() : super.created();
-
-  bool get applyAuthorStyles => true;
-
-  ShadowRoot get _shadowRoot => getShadowRoot('editable-label');
-
-  InputElement get _editBox => _shadowRoot.query('#edit');
-
-  void edit() {
-    editing = true;
-
-    // Wait for _editBox to be inserted.
-    onMutation(_shadowRoot).then((_) {
-      // For IE and Firefox: use .focus(), then reset the value to move the
-      // cursor to the end.
-      _editBox.focus();
-      _editBox.value = '';
-      _editBox.value = value;
-    });
-  }
-
-  void update(Event e) {
-    e.preventDefault(); // don't submit the form
-    if (!editing) return; // bail if user canceled
-    value = _editBox.value;
-    editing = false;
-  }
-
-  void maybeCancel(KeyboardEvent e) {
-    if (e.keyCode == KeyCode.ESC) {
-      editing = false;
-    }
-  }
-}
-
-@initMethod
-void _init() {
-  Polymer.register('editable-label', EditableLabel);
-}