Use constexpr TaskTraits constructor in chrome.

chrome/browser/chromeos/system_logs/debug_log_writer.cc

Index: chrome/browser/chromeos/system_logs/debug_log_writer.cc
diff --git a/chrome/browser/chromeos/system_logs/debug_log_writer.cc b/chrome/browser/chromeos/system_logs/debug_log_writer.cc
index e7d4b6541d06762f598d59f44b830a22139edf89..671a826ff3d8da6c7bec79a01b0967d23e582ff0 100644
--- a/chrome/browser/chromeos/system_logs/debug_log_writer.cc
+++ b/chrome/browser/chromeos/system_logs/debug_log_writer.cc
@@ -196,9 +196,7 @@ void OnSystemLogsAdded(const DebugLogWriter::StoreLogsCallback& callback,
       logging::GetSessionLogDir(*base::CommandLine::ForCurrentProcess());
 
   base::PostTaskWithTraits(
-      FROM_HERE,
-      base::TaskTraits().MayBlock().WithPriority(
-          base::TaskPriority::BACKGROUND),
+      FROM_HERE, {base::MayBlock(), base::TaskPriority::BACKGROUND},
       base::Bind(&AddUserLogsToArchive, user_log_dir, tar_file_path,
                  compressed_output_path, callback));
 }