Use constexpr TaskTraits constructor in chrome.

chrome/browser/supervised_user/experimental/supervised_user_blacklist.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/supervised_user/experimental/supervised_user_blacklist.h"
 
 #include <algorithm>
 #include <cstring>
 #include <fstream>
 
@@ skipping 54 matching lines @@
 }
 
 size_t SupervisedUserBlacklist::GetEntryCount() const {
   return host_hashes_.size();
 }
 
 void SupervisedUserBlacklist::ReadFromFile(const base::FilePath& path,
                                            const base::Closure& done_callback) {
   base::PostTaskWithTraitsAndReplyWithResult(
       FROM_HERE,
-      base::TaskTraits()
-          .MayBlock()
-          .WithPriority(base::TaskPriority::BACKGROUND)
-          .WithShutdownBehavior(
-              base::TaskShutdownBehavior::CONTINUE_ON_SHUTDOWN),
+      {base::MayBlock(), base::TaskPriority::BACKGROUND,
+       base::TaskShutdownBehavior::CONTINUE_ON_SHUTDOWN},
       base::BindOnce(&ReadFromBinaryFileOnFileThread, path),
       base::BindOnce(&SupervisedUserBlacklist::OnReadFromFileCompleted,
                      weak_ptr_factory_.GetWeakPtr(), done_callback));
 }
 
 void SupervisedUserBlacklist::OnReadFromFileCompleted(
     const base::Closure& done_callback,
     std::unique_ptr<std::vector<Hash>> host_hashes) {
   host_hashes_.swap(*host_hashes);
   LOG_IF(WARNING, host_hashes_.empty()) << "Got empty blacklist";
 
   if (!done_callback.is_null())
     done_callback.Run();
 }