Use constexpr TaskTraits constructor in chrome.

chrome/browser/chromeos/login/supervised/supervised_user_creation_controller_new.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 "chrome/browser/chromeos/login/supervised/supervised_user_creation_controller_new.h"
 
 #include "base/base64.h"
 #include "base/bind.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
@@ skipping 330 matching lines @@
   DCHECK(creation_context_);
   DCHECK_EQ(CRYPTOHOME_CREATED, stage_);
 
   stage_ = DASHBOARD_CREATED;
 
   if (error.state() == GoogleServiceAuthError::NONE) {
     creation_context_->token = token;
 
     PostTaskAndReplyWithResult(
         base::CreateTaskRunnerWithTraits(
-            base::TaskTraits()
-                .MayBlock()
-                .WithPriority(base::TaskPriority::BACKGROUND)
-                .WithShutdownBehavior(
-                    base::TaskShutdownBehavior::CONTINUE_ON_SHUTDOWN))
+            {base::MayBlock(), base::TaskPriority::BACKGROUND,
+             base::TaskShutdownBehavior::CONTINUE_ON_SHUTDOWN})
             .get(),
         FROM_HERE,
         base::Bind(&StoreSupervisedUserFiles, creation_context_->token,
                    ProfileHelper::GetProfilePathByUserIdHash(
                        creation_context_->mount_hash)),
         base::Bind(
             &SupervisedUserCreationControllerNew::OnSupervisedUserFilesStored,
             weak_factory_.GetWeakPtr()));
   } else {
     stage_ = STAGE_ERROR;
@@ skipping 50 matching lines @@
   creation_context_->registration_utility.reset();
   chrome::AttemptUserExit();
 }
 
 std::string SupervisedUserCreationControllerNew::GetSupervisedUserId() {
   DCHECK(creation_context_);
   return creation_context_->local_user_id;
 }
 
 }  // namespace chromeos