[pinpoint] Add iron-form and paper-checkbox to polymer components.

third_party/polymer/components/iron-form/test/validatable-element-with-nested-elements.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-form-element-behavior/iron-form-element-behavior.html">
+
+<dom-module id="validatable-element-with-nested-elements">
+  <template>
+    <content></content>
+  </template>
+</dom-module>
+
+<script>
+
+  Polymer({
+
+    is: 'validatable-element-with-nested-elements',
+
+    behaviors: [
+      Polymer.IronFormElementBehavior
+    ],
+
+    validate: function() {
+      return true;
+    },
+
+  });
+
+</script>