Update settings.html and settings.js to Polymer 0.8

chrome/browser/resources/settings/settings.js

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @fileoverview
  * 'cr-settings' is the main MD-Settings element, combining the UI and models.
  *
  * Example:
  *
  *    <cr-settings></cr-settings>
  *
  * @group Chrome Settings Elements
  * @element cr-settings
  */
-Polymer('cr-settings', {});
+Polymer({
+  is: 'cr-settings',
+
+  properties {
+    /**
+     * The CrSettingsPrefsElement used throughout the app.
+     * @private {!CrSettingsPrefsElement}
+     */
+    prefs_: {
+      type: Object,
+      value: function() { return this.$.prefs; },
+      notify: true,
+    }
+  },
+});