Use constexpr TaskTraits constructor in chrome.

chrome/browser/ui/webui/about_ui.cc

Index: chrome/browser/ui/webui/about_ui.cc
diff --git a/chrome/browser/ui/webui/about_ui.cc b/chrome/browser/ui/webui/about_ui.cc
index 8e2d401e7b470bb2afae0cba4a8e486b5be415a9..f3922f56d613c51e0fb37d7e47c0b815d8aef486 100644
--- a/chrome/browser/ui/webui/about_ui.cc
+++ b/chrome/browser/ui/webui/about_ui.cc
@@ -320,8 +320,7 @@ class ChromeOSCreditsHandler
     }
     // Load local Chrome OS credits from the disk.
     base::PostTaskWithTraitsAndReply(
-        FROM_HERE, base::TaskTraits().MayBlock().WithPriority(
-                       base::TaskPriority::BACKGROUND),
+        FROM_HERE, {base::MayBlock(), base::TaskPriority::BACKGROUND},
         base::Bind(&ChromeOSCreditsHandler::LoadCreditsFileAsync, this),
         base::Bind(&ChromeOSCreditsHandler::ResponseOnUIThread, this));
   }