[DevTools] Remove Common.Event.target field.

third_party/WebKit/Source/devtools/front_end/main/OverlayController.js

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 /**
  * @unrestricted
  */
 Main.OverlayController = class {
   constructor() {
     Common.moduleSetting('disablePausedStateOverlay').addChangeListener(this._updateAllOverlays, this);
     SDK.targetManager.addModelListener(
@@ skipping 10 matching lines @@
     for (var target of SDK.targetManager.targets(SDK.Target.Capability.Browser)) {
       this._updateTargetOverlay(
           /** @type {!SDK.DebuggerModel} */ (SDK.DebuggerModel.fromTarget(target)));
     }
   }
 
   /**
    * @param {!Common.Event} event
    */
   _updateOverlay(event) {
-    this._updateTargetOverlay(/** @type {!SDK.DebuggerModel} */ (event.target));
+    this._updateTargetOverlay(/** @type {!SDK.DebuggerModel} */ (event.data));
   }
 
   /**
    * @param {!SDK.DebuggerModel} debuggerModel
    */
   _updateTargetOverlay(debuggerModel) {
     if (!debuggerModel.target().hasBrowserCapability())
       return;
     var message = debuggerModel.isPaused() && !Common.moduleSetting('disablePausedStateOverlay').get() ?
         Common.UIString('Paused in debugger') :
         undefined;
     debuggerModel.target().pageAgent().configureOverlay(SDK.targetManager.allTargetsSuspended(), message);
   }
 };