Remove content::kFontListSequenceToken.

content/common/font_list.cc

 // Copyright 2013 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 "content/common/font_list.h"
 
+#include "base/lazy_instance.h"
+#include "base/task_scheduler/post_task.h"
+
 namespace content {
-const char kFontListSequenceToken[] = "_font_list_sequence_token_";
+
+namespace {
+
+struct FontListTaskRunner {
+  const scoped_refptr<base::SequencedTaskRunner> task_runner =
+      base::CreateSequencedTaskRunnerWithTraits(
+          {base::MayBlock(), base::TaskPriority::USER_VISIBLE});
+};
+
+base::LazyInstance<FontListTaskRunner>::Leaky g_font_list_task_runner =
+    LAZY_INSTANCE_INITIALIZER;
+
+}  // namespace
+
+scoped_refptr<base::SequencedTaskRunner> GetFontListTaskRunner() {
+  return g_font_list_task_runner.Get().task_runner;
 }
+
+}  // content