Add a helper method to create SW SimpleEventCallbacks.

content/browser/service_worker/service_worker_version_unittest.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 "content/browser/service_worker/service_worker_version.h"
 
 #include <stdint.h>
 #include <tuple>
 
 #include "base/macros.h"
@@ skipping 896 matching lines @@
 
   // Create a request.
   int request_id =
       version_->StartRequest(ServiceWorkerMetrics::EventType::FETCH_MAIN_FRAME,
                              CreateReceiverOnCurrentThread(&error_status));
 
   // Dispatch a dummy event whose response will be received by SWVersion.
   EXPECT_FALSE(extendable_message_event_callback());
   version_->event_dispatcher()->DispatchExtendableMessageEvent(
       mojom::ExtendableMessageEvent::New(),
-      base::Bind(&ServiceWorkerVersion::OnSimpleEventFinished, version_,
-                 request_id));
+      version_->CreateSimpleEventCallback(request_id));
+
   base::RunLoop().RunUntilIdle();
   // The renderer should have received an ExtendableMessageEvent request.
   EXPECT_TRUE(extendable_message_event_callback());
 
   // Callback has not completed yet.
   EXPECT_EQ(SERVICE_WORKER_ERROR_NETWORK, error_status);
   EXPECT_EQ(EmbeddedWorkerStatus::RUNNING, version_->running_status());
 
   // Simulate timeout.
   EXPECT_FALSE(stop_worker_callback());
@@ skipping 926 matching lines @@
   histogram_tester_.ExpectTotalCount(kLinkMouseDown, 1);
   histogram_tester_.ExpectTotalCount(kLinkTapDown, 0);
   EXPECT_EQ(SERVICE_WORKER_OK, status);
   StopWorker();
   // The UMA for kLinkMouseDown must be recorded when the worker stopped.
   histogram_tester_.ExpectTotalCount(kLinkMouseDown, 1);
   histogram_tester_.ExpectTotalCount(kLinkTapDown, 1);
 }
 
 }  // namespace content