Revert of [DevTools] Remove methods on Common.Event.

third_party/WebKit/Source/devtools/front_end/components/DockController.js

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 22 matching lines @@
  */
 Components.DockController = class extends Common.Object {
   /**
    * @param {boolean} canDock
    */
   constructor(canDock) {
     super();
     this._canDock = canDock;
 
     this._closeButton = new UI.ToolbarButton(Common.UIString('Close'), 'largeicon-delete');
-    this._closeButton.addEventListener(
-        UI.ToolbarButton.Events.Click, InspectorFrontendHost.closeWindow.bind(InspectorFrontendHost));
+    this._closeButton.addEventListener('click', InspectorFrontendHost.closeWindow.bind(InspectorFrontendHost));
 
     if (!canDock) {
       this._dockSide = Components.DockController.State.Undocked;
       this._updateUI();
       return;
     }
 
     this._states = [
       Components.DockController.State.DockedToRight, Components.DockController.State.DockedToBottom,
       Components.DockController.State.Undocked
@@ skipping 159 matching lines @@
    */
   item() {
     return Components.dockController._closeButton;
   }
 };
 
 /**
  * @type {!Components.DockController}
  */
 Components.dockController;