Use constexpr TaskTraits constructor in chrome.

chrome/browser/ui/views/tabs/browser_tab_strip_controller.cc

 // Copyright (c) 2012 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/ui/views/tabs/browser_tab_strip_controller.h"
 
 #include "base/auto_reset.h"
 #include "base/macros.h"
 #include "base/metrics/user_metrics.h"
 #include "base/task_scheduler/post_task.h"
@@ skipping 396 matching lines @@
             ImmersiveModeController::ANIMATE_REVEAL_NO));
   }
 }
 
 void BrowserTabStripController::OnStoppedDraggingTabs() {
   immersive_reveal_lock_.reset();
 }
 
 void BrowserTabStripController::CheckFileSupported(const GURL& url) {
   base::PostTaskWithTraitsAndReplyWithResult(
-      FROM_HERE, base::TaskTraits().MayBlock().WithPriority(
-                     base::TaskPriority::USER_VISIBLE),
+      FROM_HERE, {base::MayBlock(), base::TaskPriority::USER_VISIBLE},
       base::Bind(&FindURLMimeType, url),
       base::Bind(&BrowserTabStripController::OnFindURLMimeTypeCompleted,
                  weak_ptr_factory_.GetWeakPtr(), url));
 }
 
 SkColor BrowserTabStripController::GetToolbarTopSeparatorColor() const {
   return browser_view_->frame()->GetFrameView()->GetToolbarTopSeparatorColor();
 }
 
 base::string16 BrowserTabStripController::GetAccessibleTabName(
@@ skipping 153 matching lines @@
   content::WebPluginInfo plugin;
   tabstrip_->FileSupported(
       url,
       mime_type.empty() || mime_util::IsSupportedMimeType(mime_type) ||
           content::PluginService::GetInstance()->GetPluginInfo(
               -1,                // process ID
               MSG_ROUTING_NONE,  // routing ID
               model_->profile()->GetResourceContext(), url, url::Origin(),
               mime_type, false, NULL, &plugin, NULL));
 }