Use constexpr TaskTraits constructor in chrome.

chrome/browser/io_thread.cc

 // Copyright (c) 2012 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 "chrome/browser/io_thread.h"
 
 #include <utility>
 #include <vector>
 
 #include "base/base64.h"
@@ skipping 1063 matching lines @@
 
   std::unique_ptr<net::URLRequestJobFactoryImpl> job_factory(
       new net::URLRequestJobFactoryImpl());
 
   job_factory->SetProtocolHandler(url::kDataScheme,
                                   base::MakeUnique<net::DataProtocolHandler>());
   job_factory->SetProtocolHandler(
       url::kFileScheme,
       base::MakeUnique<net::FileProtocolHandler>(
           base::CreateTaskRunnerWithTraits(
-              base::TaskTraits()
-                  .MayBlock()
-                  .WithPriority(base::TaskPriority::USER_VISIBLE)
-                  .WithShutdownBehavior(
-                      base::TaskShutdownBehavior::SKIP_ON_SHUTDOWN))));
+              {base::MayBlock(), base::TaskPriority::USER_VISIBLE,
+               base::TaskShutdownBehavior::SKIP_ON_SHUTDOWN})));
 #if !BUILDFLAG(DISABLE_FTP_SUPPORT)
   job_factory->SetProtocolHandler(
       url::kFtpScheme,
       net::FtpProtocolHandler::Create(globals->host_resolver.get()));
 #endif
   globals->proxy_script_fetcher_url_request_job_factory =
       std::move(job_factory);
 
   context->set_job_factory(
       globals->proxy_script_fetcher_url_request_job_factory.get());
 
   // TODO(rtenneti): We should probably use HttpServerPropertiesManager for the
   // system URLRequestContext too. There's no reason this should be tied to a
   // profile.
   return context;
 }
 
 metrics::UpdateUsagePrefCallbackType IOThread::GetMetricsDataUseForwarder() {
   return base::Bind(&UpdateMetricsUsagePrefsOnUIThread);
 }