Force a rescan when opening the Wifi menu on the settings page.

chrome/browser/resources/options2/chromeos/network_list.js

 // Copyright (c) 2012 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.network', function() {
 
   var ArrayDataModel = cr.ui.ArrayDataModel;
   var List = cr.ui.List;
   var ListItem = cr.ui.ListItem;
   var Menu = cr.ui.Menu;
@@ skipping 291 matching lines @@
         return menu;
       }
       return null;
     },
 
     /**
      * Displays a popup menu.
      */
     showMenu: function() {
       var rebuild = false;
+      // Force a rescan if opening the menu for WiFi networks to ensure the
+      // list is up to date. Networks are periodically rescanned, but depending
+      // on timing, there could be an excessive delay before the first rescan
+      // unless forced.
+      var rescan = !activeMenu_ && this.data_.key == 'wifi';
       if (!this.menu_) {
         rebuild = true;
         var existing = $(this.getMenuName_());
         if (existing)
           closeMenu_();
         this.menu_ = this.createMenu();
         var parent = $('network-menus');
         if (existing)
           parent.replaceChild(this.menu_, existing);
         else
           parent.appendChild(this.menu_);
       }
       var top = this.offsetTop + this.clientHeight;
       var menuId = this.getMenuName_();
       if (menuId != activeMenu_ || rebuild) {
         closeMenu_();
         activeMenu_ = menuId;
         this.menu_.style.setProperty('top', top + 'px');
         this.menu_.hidden = false;
       }
+      if (rescan)
+        chrome.send('refreshNetworksCallback');
     },
   };
 
   /**
    * Creates a control for selecting or configuring a network connection based
    * on the type of connection (e.g. wifi versus vpn).
    * @param {{key: string,
    *          networkList: Array.<Object>} data  Description of the network.
    * @constructor
    */
@@ skipping 658 matching lines @@
    * Whether the Network list is disabled. Only used for display purpose.
    * @type {boolean}
    */
   cr.defineProperty(NetworkList, 'disabled', cr.PropertyKind.BOOL_ATTR);
 
   // Export
   return {
     NetworkList: NetworkList
   };
 });