Issue 3868 - Use the new FilterNotifier API

lib/messaging.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2016 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 19 matching lines @@
 {
   this._eventEmitter = new EventEmitter();
   this._onMessage = this._onMessage.bind(this);
   ext.onMessage.addListener(this._onMessage);
 };
 
 Port.prototype = {
   _onMessage: function(message, sender, sendResponse)
   {
     let async = false;
-    let callbacks = this._eventEmitter._listeners[message.type];
+    let callbacks = this._eventEmitter.listeners(message.type);
 
-    if (callbacks)
+    for (let callback of callbacks)
     {
-      for (let callback of callbacks)
+      let response = callback(message, sender);
+
+      if (response && typeof response.then == "function")
       {
-        let response = callback(message, sender);
-
-        if (response && typeof response.then == "function")
-        {
-          response.then(
-            sendResponse,
-            reason => {
-              console.error(reason);
-              sendResponse(undefined);
-            }
-          );
-          async = true;
-        }
-        else if (typeof response != "undefined")
-        {
-          sendResponse(response);
-        }
+        response.then(
+          sendResponse,
+          reason => {
+            console.error(reason);
+            sendResponse(undefined);
+          }
+        );
+        async = true;
+      }
+      else if (typeof response != "undefined")
+      {
+        sendResponse(response);
       }
     }
 
     return async;
   },
 
   /**
    * Function to be called when a particular message is received.
    *
    * @callback Port~messageCallback
@@ skipping 52 matching lines @@
 exports.getPort = function(window)
 {
   let port = new Port();
   window.addEventListener("unload", () =>
   {
     port.disconnect();
   });
   return port;
 };