Introduce ServiceWorker.EventDispatchingDelay UMA

content/browser/service_worker/service_worker_browsertest.cc

 // 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.
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <map>
 #include <memory>
 #include <utility>
@@ skipping 651 matching lines @@
             request_id, base::Bind(&self::ReceiveInstallEventOnIOThread,
                                    base::Unretained(this), done, result));
     version_->DispatchEvent({request_id},
                             ServiceWorkerMsg_InstallEvent(request_id));
   }
 
   void ReceiveInstallEventOnIOThread(const base::Closure& done,
                                      ServiceWorkerStatusCode* out_result,
                                      int request_id,
                                      blink::WebServiceWorkerEventResult result,
-                                     bool has_fetch_handler) {
+                                     bool has_fetch_handler,
+                                     base::Time dispatch_event_time) {
     version_->FinishRequest(
-        request_id, result == blink::WebServiceWorkerEventResultCompleted);
+        request_id, result == blink::WebServiceWorkerEventResultCompleted,
+        dispatch_event_time);
     version_->set_fetch_handler_existence(
         has_fetch_handler
             ? ServiceWorkerVersion::FetchHandlerExistence::EXISTS
             : ServiceWorkerVersion::FetchHandlerExistence::DOES_NOT_EXIST);
 
     ServiceWorkerStatusCode status = SERVICE_WORKER_OK;
     if (result == blink::WebServiceWorkerEventResultRejected)
       status = SERVICE_WORKER_ERROR_EVENT_WAITUNTIL_REJECTED;
 
     *out_result = status;
@@ skipping 1338 matching lines @@
 
 IN_PROC_BROWSER_TEST_F(ServiceWorkerDisableWebSecurityTest, UpdateNoCrash) {
   const char kPageUrl[] = "/service_worker/disable_web_security_update.html";
   const char kScopeUrl[] = "/service_worker/scope/";
   const char kWorkerUrl[] = "/service_worker/fetch_event_blob.js";
   RegisterServiceWorkerOnCrossOriginServer(kScopeUrl, kWorkerUrl);
   RunTestWithCrossOriginURL(kPageUrl, kScopeUrl);
 }
 
 }  // namespace content