Use XMLHttpRequest.status instead of nsIHttpChannel.responseStatus(same value, better cross-browse…

lib/downloader.js

 /*
  * This file is part of Adblock Plus <http://adblockplus.org/>,
  * Copyright (C) 2006-2013 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 200 matching lines @@
     let request = null;
 
     let errorCallback = function errorCallback(error)
     {
       let channelStatus = -1;
       try
       {
         channelStatus = request.channel.status;
       } catch (e) {}
 
-      let responseStatus = -1;
-      try
-      {
-        responseStatus = request.status;
-      } catch (e) {}
+      let responseStatus = request.status;
 
       Cu.reportError("Adblock Plus: Downloading URL " + downloadable.url + " failed (" + error + ")\n" +
                      "Download address: " + downloadURL + "\n" +
                      "Channel status: " + channelStatus + "\n" +
                      "Server response: " + responseStatus);
 
       if (this.onDownloadError)
       {
         // Allow one extra redirect if the error handler gives us a redirect URL
         let redirectCallback = null;
@@ skipping 140 matching lines @@
    * @type Integer
    */
   softExpiration: 0,
 
   /**
    * Hard expiration interval, this is fixed.
    * @type Integer
    */
   hardExpiration: 0,
 };