Use constexpr TaskTraits constructor in chrome.

chrome/browser/browsing_data/site_data_size_collector.cc

 // Copyright 2016 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/browsing_data/site_data_size_collector.h"
 
 #include "base/files/file_util.h"
 #include "base/task_scheduler/post_task.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/pref_names.h"
@@ skipping 129 matching lines @@
     const net::CookieList& cookie_list) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
 
   if (cookie_list.empty()) {
     OnStorageSizeFetched(0);
     return;
   }
   base::FilePath cookie_file_path = default_storage_partition_path_
       .Append(chrome::kCookieFilename);
   base::PostTaskWithTraitsAndReplyWithResult(
-      FROM_HERE, base::TaskTraits().MayBlock().WithPriority(
-                     base::TaskPriority::BACKGROUND),
+      FROM_HERE, {base::MayBlock(), base::TaskPriority::BACKGROUND},
       base::Bind(&GetFileSizeBlocking, cookie_file_path),
       base::Bind(&SiteDataSizeCollector::OnStorageSizeFetched,
                  weak_ptr_factory_.GetWeakPtr()));
 }
 
 void SiteDataSizeCollector::OnDatabaseModelInfoLoaded(
     const DatabaseInfoList& database_info_list) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   int64_t total_size = 0;
   for (const auto& database_info : database_info_list)
@@ skipping 34 matching lines @@
     const ChannelIDList& channel_id_list) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
 
   if (channel_id_list.empty()) {
     OnStorageSizeFetched(0);
     return;
   }
   base::FilePath channel_id_file_path = default_storage_partition_path_
       .Append(chrome::kChannelIDFilename);
   base::PostTaskWithTraitsAndReplyWithResult(
-      FROM_HERE, base::TaskTraits().MayBlock().WithPriority(
-                     base::TaskPriority::BACKGROUND),
+      FROM_HERE, {base::MayBlock(), base::TaskPriority::BACKGROUND},
       base::Bind(&GetFileSizeBlocking, channel_id_file_path),
       base::Bind(&SiteDataSizeCollector::OnStorageSizeFetched,
                  weak_ptr_factory_.GetWeakPtr()));
 }
 
 void SiteDataSizeCollector::OnServiceWorkerModelInfoLoaded(
     const ServiceWorkerUsageInfoList& service_worker_info_list) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   int64_t total_size = 0;
   for (const auto& service_worker_info : service_worker_info_list)
@@ skipping 16 matching lines @@
 
   // TODO(fukino): Flash is not the only plugin. We should check all types of
   // plugin data.
   if (domains.empty()) {
     OnStorageSizeFetched(0);
     return;
   }
   base::FilePath pepper_data_dir_path = default_storage_partition_path_
       .Append(content::kPepperDataDirname);
   base::PostTaskWithTraitsAndReplyWithResult(
-      FROM_HERE, base::TaskTraits().MayBlock().WithPriority(
-                     base::TaskPriority::BACKGROUND),
+      FROM_HERE, {base::MayBlock(), base::TaskPriority::BACKGROUND},
       base::Bind(&base::ComputeDirectorySize, pepper_data_dir_path),
       base::Bind(&SiteDataSizeCollector::OnStorageSizeFetched,
                  weak_ptr_factory_.GetWeakPtr()));
 }
 
 void SiteDataSizeCollector::OnStorageSizeFetched(int64_t size) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   if (size > 0)
     total_bytes_ += size;
   if (--in_flight_operations_ == 0)
     fetch_callback_.Run(total_bytes_);
 }