Only show prefer network checkbox for networks stored on user profile.

chrome/browser/resources/options/chromeos/internet_detail.js

 // Copyright (c) 2011 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.
 
 cr.define('options.internet', function() {
   var OptionsPage = options.OptionsPage;
 
   /*
    * Helper function to set hidden attribute on given element list.
    * @param {Array} elements List of elements to be updated.
@@ skipping 76 matching lines @@
           cr.doc.querySelectorAll('#detailsInternetPage .apn-details-view'),
           true);
 
       // Password and shared.
       updateHidden(
           cr.doc.querySelectorAll('#detailsInternetPage .password-details'),
           !this.wireless || !this.password);
       updateHidden(
           cr.doc.querySelectorAll('#detailsInternetPage .shared-network'),
           !this.shared);
+      updateHidden(
+          cr.doc.querySelectorAll('#detailsInternetPage .prefer-network'),
+          !this.showPreferred);
     }
   };
 
   /**
    * Whether the underlying network is connected. Only used for display purpose.
    * @type {boolean}
    */
   cr.defineProperty(DetailsInternetPage, 'connected',
       cr.PropertyKind.JS,
       DetailsInternetPage.prototype.updateControls_);
@@ skipping 85 matching lines @@
       cr.PropertyKind.JS);
   cr.defineProperty(DetailsInternetPage, 'connecting',
       cr.PropertyKind.JS);
   cr.defineProperty(DetailsInternetPage, 'connected',
       cr.PropertyKind.JS);
 
   return {
     DetailsInternetPage: DetailsInternetPage
   };
 });