ServiceWorker: Store the existence of fetch event handler

content/common/service_worker/service_worker_messages.h

 // 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.
 
 // Message definition file, included multiple times, hence no include guard.
 
 #include <stdint.h>
 
 #include <string>
 #include <vector>
@@ skipping 224 matching lines @@
 
 // Informs the browser that |provider_id| is associated
 // with a service worker script running context and
 // |version_id| identifies which ServiceWorkerVersion.
 IPC_MESSAGE_CONTROL2(ServiceWorkerHostMsg_SetVersionId,
                      int /* provider_id */,
                      int64_t /* version_id */)
 
 // Informs the browser that event handling has finished.
 // Routed to the target ServiceWorkerVersion.
-IPC_MESSAGE_ROUTED2(ServiceWorkerHostMsg_InstallEventFinished,
+IPC_MESSAGE_ROUTED3(ServiceWorkerHostMsg_InstallEventFinished,
                     int /* request_id */,
-                    blink::WebServiceWorkerEventResult)
+                    blink::WebServiceWorkerEventResult,
+                    bool /* has_fetch_event_handler */)
+
 IPC_MESSAGE_ROUTED2(ServiceWorkerHostMsg_ActivateEventFinished,
                     int /* request_id */,
                     blink::WebServiceWorkerEventResult)
 IPC_MESSAGE_ROUTED2(ServiceWorkerHostMsg_ExtendableMessageEventFinished,
                     int /* request_id */,
                     blink::WebServiceWorkerEventResult)
 IPC_MESSAGE_ROUTED3(ServiceWorkerHostMsg_FetchEventFinished,
                     int /* request_id */,
                     content::ServiceWorkerFetchEventResult,
                     content::ServiceWorkerResponse)
@@ skipping 261 matching lines @@
 
 // Sent via EmbeddedWorker as a response of NavigateClient.
 IPC_MESSAGE_CONTROL2(ServiceWorkerMsg_NavigateClientResponse,
                      int /* request_id */,
                      content::ServiceWorkerClientInfo /* client */)
 
 // Sent via EmbeddedWorker as an error response of NavigateClient.
 IPC_MESSAGE_CONTROL2(ServiceWorkerMsg_NavigateClientError,
                      int /* request_id */,
                      GURL /* url */)