[third_party] add polymer 1.2.3

polymer_1.2.3/bower_components/iron-form-element-behavior/test/simple-form.html

 <!--
 @license
 Copyright (c) 2015 The Polymer Project Authors. All rights reserved.
 This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
 The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
 The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
 Code distributed by Google as part of the polymer project is also
 subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
 -->
-
 <link rel="import" href="../../polymer/polymer.html">
-<link rel="import" href="../iron-validator-behavior.html">
 
 <script>
 
   Polymer({
-
-    is: 'simple-validator',
-
-    behaviors: [
-      Polymer.IronValidatorBehavior
-    ]
-
+    is: 'simple-form',
+    extends: 'form'
   });
 
 </script>