Issue 6854 - Remove deprecated FilterNotifier methods

lib/synchronizer.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-present 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 124 matching lines @@
       downloadable.softExpiration / MILLIS_IN_SECOND
     );
     subscription.expires = Math.round(
       downloadable.hardExpiration / MILLIS_IN_SECOND
     );
   },
 
   _onDownloadStarted(downloadable)
   {
     let subscription = Subscription.fromURL(downloadable.url);
-    FilterNotifier.triggerListeners("subscription.downloading", subscription);
+    FilterNotifier.emit("subscription.downloading", subscription);
   },
 
   _onDownloadSuccess(downloadable, responseText, errorCallback,
                      redirectCallback)
   {
     let lines = responseText.split(/[\r\n]+/);
     let headerMatch = /\[Adblock(?:\s*Plus\s*([\d.]+)?)?\]/i.exec(lines[0]);
     if (!headerMatch)
       return errorCallback("synchronize_invalid_data");
     let minVersion = headerMatch[1];
@@ skipping 192 matching lines @@
               subscription.filters.map(f => f.text).join("\n");
             redirectCallback("data:text/plain," + encodeURIComponent(data));
           }
         }, false);
         request.send(null);
       }
     }
   }
 };
 Synchronizer.init();