--- a/devtools/client/debugger/debugger-controller.js
+++ b/devtools/client/debugger/debugger-controller.js
@@ -101,17 +101,17 @@ const { require } = BrowserLoader({
 });
 const { XPCOMUtils } = require("resource://gre/modules/XPCOMUtils.jsm");
 XPCOMUtils.defineConstant(this, "require", require);
 const { SimpleListWidget } = require("resource://devtools/client/shared/widgets/SimpleListWidget.jsm");
 const { BreadcrumbsWidget } = require("resource://devtools/client/shared/widgets/BreadcrumbsWidget.jsm");
 const { SideMenuWidget } = require("resource://devtools/client/shared/widgets/SideMenuWidget.jsm");
 const { VariablesView } = require("resource://devtools/client/shared/widgets/VariablesView.jsm");
 const { VariablesViewController, StackFrameUtils } = require("resource://devtools/client/shared/widgets/VariablesViewController.jsm");
-const EventEmitter = require("devtools/shared/old-event-emitter");
+const EventEmitter = require("devtools/shared/event-emitter");
 const { extend } = require("devtools/shared/extend");
 const { gDevTools } = require("devtools/client/framework/devtools");
 const { ViewHelpers, WidgetMethods, setNamedTimeout,
         clearNamedTimeout } = require("devtools/client/shared/widgets/view-helpers");
 
 // Use privileged promise in panel documents to prevent having them to freeze
 // during toolbox destruction. See bug 1402779.
 const Promise = require("Promise");
@@ -445,17 +445,17 @@ var DebuggerController = {
                             action.status === "done"),
       run: deferred.resolve
     });
     return deferred.promise;
   },
 
   waitForSourceShown: function (name) {
     const deferred = promise.defer();
-    window.on(EVENTS.SOURCE_SHOWN, function onShown(_, source) {
+    window.on(EVENTS.SOURCE_SHOWN, function onShown(source) {
       if (source.url.includes(name)) {
         window.off(EVENTS.SOURCE_SHOWN, onShown);
         deferred.resolve();
       }
     });
     return deferred.promise;
   },
 

--- a/devtools/client/debugger/panel.js
+++ b/devtools/client/debugger/panel.js
@@ -2,17 +2,17 @@
 /* vim: set ft=javascript ts=2 et sw=2 tw=80: */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 "use strict";
 
 const { Cc, Ci, Cu, Cr } = require("chrome");
 const promise = require("promise");
-const EventEmitter = require("devtools/shared/old-event-emitter");
+const EventEmitter = require("devtools/shared/event-emitter");
 const DevToolsUtils = require("devtools/shared/DevToolsUtils");
 
 function DebuggerPanel(iframeWindow, toolbox) {
   this.panelWin = iframeWindow;
   this._toolbox = toolbox;
   this._destroyer = null;
 
   this._view = this.panelWin.DebuggerView;

--- a/devtools/client/debugger/test/mochitest/head.js
+++ b/devtools/client/debugger/test/mochitest/head.js
@@ -14,17 +14,17 @@ Services.scriptloader.loadSubScript("chr
 var gEnableLogging = Services.prefs.getBoolPref("devtools.debugger.log");
 Services.prefs.setBoolPref("devtools.debugger.log", false);
 
 var { BrowserToolboxProcess } = ChromeUtils.import("resource://devtools/client/framework/ToolboxProcess.jsm", {});
 var { DebuggerServer } = require("devtools/server/main");
 var { DebuggerClient } = require("devtools/shared/client/debugger-client");
 var ObjectClient = require("devtools/shared/client/object-client");
 var { AddonManager } = ChromeUtils.import("resource://gre/modules/AddonManager.jsm", {});
-var EventEmitter = require("devtools/shared/old-event-emitter");
+var EventEmitter = require("devtools/shared/event-emitter");
 var { Toolbox } = require("devtools/client/framework/toolbox");
 var { Task } = require("devtools/shared/task");
 
 const chromeRegistry = Cc["@mozilla.org/chrome/chrome-registry;1"].getService(Ci.nsIChromeRegistry);
 
 // Override promise with deprecated-sync-thenables
 promise = require("devtools/shared/deprecated-sync-thenables");
 
@@ -375,17 +375,17 @@ function waitForSourceAndCaretAndScopes(
 
 function waitForDebuggerEvents(aPanel, aEventName, aEventRepeat = 1) {
   info("Waiting for debugger event: '" + aEventName + "' to fire: " + aEventRepeat + " time(s).");
 
   let deferred = promise.defer();
   let panelWin = aPanel.panelWin;
   let count = 0;
 
-  panelWin.on(aEventName, function onEvent(aEventName, ...aArgs) {
+  panelWin.on(aEventName, function onEvent(...aArgs) {
     info("Debugger event '" + aEventName + "' fired: " + (++count) + " time(s).");
 
     if (count == aEventRepeat) {
       ok(true, "Enough '" + aEventName + "' panel events have been fired.");
       panelWin.off(aEventName, onEvent);
       deferred.resolve.apply(deferred, aArgs);
     }
   });