Use constexpr TaskTraits constructor in content.

content/browser/net/quota_policy_cookie_store.cc

Index: content/browser/net/quota_policy_cookie_store.cc
diff --git a/content/browser/net/quota_policy_cookie_store.cc b/content/browser/net/quota_policy_cookie_store.cc
index 0c931e2ea858de338b244a6fe4291365c7e174c1..dd3f35982cca13a61892d8cc1f2b16182ce6d4f8 100644
--- a/content/browser/net/quota_policy_cookie_store.cc
+++ b/content/browser/net/quota_policy_cookie_store.cc
@@ -155,8 +155,7 @@ std::unique_ptr<net::CookieStore> CreateCookieStore(
 
     if (!background_task_runner.get()) {
       background_task_runner = base::CreateSequencedTaskRunnerWithTraits(
-          base::TaskTraits().MayBlock().WithPriority(
-              base::TaskPriority::BACKGROUND));
+          {base::MayBlock(), base::TaskPriority::BACKGROUND});
     }
 
     scoped_refptr<net::SQLitePersistentCookieStore> sqlite_store(