Use constexpr TaskTraits constructor in chrome.

chrome/browser/ui/views/frame/taskbar_decorator_win.cc

Index: chrome/browser/ui/views/frame/taskbar_decorator_win.cc
diff --git a/chrome/browser/ui/views/frame/taskbar_decorator_win.cc b/chrome/browser/ui/views/frame/taskbar_decorator_win.cc
index 85dafebf1a3104083654973e05f7015dbe9404e9..a00785432a25e760efd71ff29d4e94c625dcea81 100644
--- a/chrome/browser/ui/views/frame/taskbar_decorator_win.cc
+++ b/chrome/browser/ui/views/frame/taskbar_decorator_win.cc
@@ -88,8 +88,7 @@ void DrawTaskbarDecoration(gfx::NativeWindow window, const gfx::Image* image) {
   // TODO(robliao): Annotate this task with .WithCOM() once supported.
   // https://crbug.com/662122
   base::PostTaskWithTraits(
-      FROM_HERE, base::TaskTraits().MayBlock().WithPriority(
-                     base::TaskPriority::USER_VISIBLE),
+      FROM_HERE, {base::MayBlock(), base::TaskPriority::USER_VISIBLE},
       base::Bind(&SetOverlayIcon, hwnd, base::Passed(&bitmap)));
 }