Update samples with latest polymer and Dartium changes

samples/third_party/todomvc/web/todo_row.html

 <!--
 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.
 -->
 <meta charset="utf-8">
 <link rel="import" href="editable_label.html">
 <polymer-element name="todo-row" extends="li">
   <template>
     <style>
@@ skipping 102 matching lines @@
     background: none;
   }
   #todo-item .toggle {
     height: 40px;
   }
 }
     </style>
     <div class="todo-item">
       <input class="toggle" type="checkbox" checked="{{todo.done}}">
       <editable-label id="label" value="{{todo.task}}"></editable-label>
-      <button class="destroy" on-click="removeTodo"></button>
+      <button class="destroy" on-click="{{removeTodo}}"></button>
     </div>
   </template>
   <script type="application/dart" src="todo_row.dart"></script>
 </polymer-element>