Import Polymer 0.8 and several key elements.

third_party/polymer/v0_8/components/iron-input/iron-input.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">
+
+<!--
+By default you can only get notified of changes to an `input`'s `value` due to user input:
+
+    <input value="{{myValue::input}}">
+
+`iron-input` adds the `bind-value` property that mirrors the `value` property, and can be used
+for two-way data binding. `bind-value` will notify if it is changed either by user input or by script.
+
+    <input is="iron-input" bind-value="{{myValue}}">
+
+-->
+<script>
+
+  Polymer({
+
+    is: 'iron-input',
+
+    extends: 'input',
+
+    properties: {
+
+      /**
+       * Use this property instead of `value` for two-way data binding.
+       */
+      bindValue: {
+        observer: '_bindValueChanged',
+        type: String
+      }
+
+    },
+
+    listeners: {
+      'input': '_onInput'
+    },
+
+    attached: function() {
+      this.bindValue = this.value;
+    },
+
+    _bindValueChanged: function() {
+      this.value = this.bindValue;
+      // manually notify because we don't want to notify until after setting value
+      this.fire('bind-value-changed', {value: this.bindValue});
+    },
+
+    _onInput: function(event) {
+      this.bindValue = event.target.value;
+    }
+
+  })
+</script>