Fix the pref binding by binding to the object rather than the element

chrome/browser/resources/settings/prefs/prefs.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-prefs' is an element which serves as a model for
  * interaction with settings which are stored in Chrome's
  * Preferences.
  *
  * Example:
  *
  *    <cr-settings-prefs id="prefs"></cr-settings-prefs>
  *    <cr-settings-a11y-page prefs="{{this.$.prefs}}"></cr-settings-a11y-page>
  *
  * @group Chrome Settings Elements
  * @element cr-settings-a11y-page
  */
 (function() {
   'use strict';
 
   Polymer({
     is: 'cr-settings-prefs',
 
     properties: {
       /**
        * Object containing all preferences.
        */
-      settings: {
+      prefStore: {
         type: Object,
         value: function() { return {}; },
         notify: true,
       },
     },
 
     /** @override */
     created: function() {
       CrSettingsPrefs.isInitialized = false;
 
@@ skipping 27 matching lines @@
 
     /**
      * Updates the settings model with the given prefs.
      * @param {!Array<!chrome.settingsPrivate.PrefObject>} prefs
      * @param {boolean} shouldObserve Whether to add an ObjectObserver for each
      *     of the prefs.
      * @private
      */
     updatePrefs_: function(prefs, shouldObserve) {
       prefs.forEach(function(prefObj) {
-        let root = this.settings;
+        let root = this.prefStore;
         let tokens = prefObj.key.split('.');
 
         assert(tokens.length > 0);
 
         for (let i = 0; i < tokens.length; i++) {
           let token = tokens[i];
 
           if (!root.hasOwnProperty(token)) {
-            let path = 'settings.' + tokens.slice(0, i + 1).join('.');
+            let path = 'prefStore.' + tokens.slice(0, i + 1).join('.');
             this.setPathValue(path, {});
           }
           root = root[token];
         }
 
         // NOTE: Do this copy rather than just a re-assignment, so that the
         // ObjectObserver fires.
         for (let objKey in prefObj) {
-          let path = 'settings.' + prefObj.key + '.' + objKey;
+          let path = 'prefStore.' + prefObj.key + '.' + objKey;
           this.setPathValue(path, prefObj[objKey]);
         }
 
         if (shouldObserve) {
           let keyObserver = new ObjectObserver(root);
           keyObserver.open(
               this.propertyChangeCallback_.bind(this, prefObj.key));
         }
       }, this);
     },
@@ skipping 21 matching lines @@
 
         chrome.settingsPrivate.setPref(
             propertyPath,
             newValue,
             /* pageId */ '',
             /* callback */ function() {});
       }
     },
   });
 })();