Add async tracing to SWVersion::AddRequest.

content/browser/background_sync/background_sync_manager.cc

 // 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.
 
 #include "content/browser/background_sync/background_sync_manager.h"
 
 #include <utility>
 
 #include "base/barrier_closure.h"
 #include "base/bind.h"
@@ skipping 108 matching lines @@
 
   background_sync_controller->GetParameterOverrides(parameters.get());
   return parameters;
 }
 
 void OnSyncEventFinished(
     const scoped_refptr<ServiceWorkerVersion>& active_version,
     int request_id,
     const ServiceWorkerVersion::StatusCallback& callback,
     ServiceWorkerEventStatus status) {
-  TRACE_EVENT1("ServiceWorker", "BackgroundSyncManager::OnSyncEventFinished",
-               "Request id", request_id);
   if (!active_version->FinishRequest(request_id))
     return;
   callback.Run(mojo::ConvertTo<ServiceWorkerStatusCode>(status));
 }
 
 }  // namespace
 
 BackgroundSyncManager::BackgroundSyncRegistrations::
     BackgroundSyncRegistrations()
     : next_id(BackgroundSyncRegistration::kInitialId) {
@@ skipping 1387 matching lines @@
 BackgroundSyncManager::MakeStatusCompletion(const StatusCallback& callback) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 
   return base::Bind(
       &BackgroundSyncManager::CompleteOperationCallback<StatusCallback,
                                                         BackgroundSyncStatus>,
       weak_ptr_factory_.GetWeakPtr(), callback);
 }
 
 }  // namespace content