Use constexpr TaskTraits constructor in chrome.

chrome/browser/ntp_snippets/content_suggestions_service_factory.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/ntp_snippets/content_suggestions_service_factory.h"
 
 #include <utility>
 
 #include "base/feature_list.h"
 #include "base/files/file_path.h"
@@ skipping 187 matching lines @@
                              PrefService* pref_service,
                              Profile* profile) {
   scoped_refptr<net::URLRequestContextGetter> request_context =
       content::BrowserContext::GetDefaultStoragePartition(profile)
           ->GetURLRequestContext();
 
   base::FilePath database_dir(
       profile->GetPath().Append(ntp_snippets::kDatabaseFolder));
   scoped_refptr<base::SequencedTaskRunner> task_runner =
       base::CreateSequencedTaskRunnerWithTraits(
-          base::TaskTraits()
-              .MayBlock()
-              .WithPriority(base::TaskPriority::BACKGROUND)
-              .WithShutdownBehavior(
-                  base::TaskShutdownBehavior::CONTINUE_ON_SHUTDOWN));
+          {base::MayBlock(), base::TaskPriority::BACKGROUND,
+           base::TaskShutdownBehavior::CONTINUE_ON_SHUTDOWN});
   std::string api_key;
   // The API is private. If we don't have the official API key, don't even try.
   if (google_apis::IsGoogleChromeAPIKeyUsed()) {
     bool is_stable_channel =
         chrome::GetChannel() == version_info::Channel::STABLE;
     api_key = is_stable_channel ? google_apis::GetAPIKey()
                                 : google_apis::GetNonStableAPIKey();
   }
 
   // Pass the pref name associated to the search suggest toggle, and use it to
@@ skipping 182 matching lines @@
           ntp_snippets::kForeignSessionsSuggestionsFeature)) {
     RegisterForeignSessionsProvider(sync_service, service, pref_service);
   }
 
   return service;
 
 #else
   return nullptr;
 #endif  // CONTENT_SUGGESTIONS_ENABLED
 }