Issue 2656 - Fixed notification shown in popup

lib/notificationHelper.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2015 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 209 matching lines @@
       if (activeNotification.type == "question")
         notificationButtonClick(approved ? 0 : 1);
       else if (approved)
         openNotificationLinks();
     }
   }
   prepareNotificationIconAndPopup();
 };
 
 /**
- * Gets the active notification to be shown.
- *
- * @return {object}
+ * Gets the active notification to be shown if any.
+ *
+ * @return {?object}
  */
 exports.getActiveNotification = function()
 {
   return activeNotification;
 };
 
 setTimeout(showNextNotification, 3 * 60 * 1000);