[DevTools] Remove Common.Event.target field.

third_party/WebKit/Source/devtools/front_end/sdk/ServiceWorkerCacheModel.js

 // Copyright 2014 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
  */
 SDK.ServiceWorkerCacheModel = class extends SDK.SDKModel {
   /**
    * Invariant: This model can only be constructed on a ServiceWorker target.
    * @param {!SDK.Target} target
@@ skipping 216 matching lines @@
    */
   _securityOriginRemoved(event) {
     var securityOrigin = /** @type {string} */ (event.data);
     this._removeOrigin(securityOrigin);
   }
 
   /**
    * @param {!SDK.ServiceWorkerCacheModel.Cache} cache
    */
   _cacheAdded(cache) {
-    this.dispatchEventToListeners(SDK.ServiceWorkerCacheModel.Events.CacheAdded, cache);
+    this.dispatchEventToListeners(SDK.ServiceWorkerCacheModel.Events.CacheAdded, {model: this, cache: cache});
   }
 
   /**
    * @param {!SDK.ServiceWorkerCacheModel.Cache} cache
    */
   _cacheRemoved(cache) {
-    this.dispatchEventToListeners(SDK.ServiceWorkerCacheModel.Events.CacheRemoved, cache);
+    this.dispatchEventToListeners(SDK.ServiceWorkerCacheModel.Events.CacheRemoved, {model: this, cache: cache});
   }
 
   /**
    * @param {!SDK.ServiceWorkerCacheModel.Cache} cache
    * @param {number} skipCount
    * @param {number} pageSize
    * @param {function(!Array.<!SDK.ServiceWorkerCacheModel.Entry>, boolean)} callback
    */
   _requestEntries(cache, skipCount, pageSize, callback) {
     /**
@@ skipping 60 matching lines @@
   }
 
   /**
    * @override
    * @return {string}
    */
   toString() {
     return this.securityOrigin + this.cacheName;
   }
 };