Revert of Use TaskScheduler instead of WorkerPool in tcp_socket_posix.cc.

net/socket/tcp_socket_posix.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 "net/socket/tcp_socket.h"
 
 #include <errno.h>
 #include <netinet/tcp.h>
 #include <sys/socket.h>
 
 #include "base/bind.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/logging.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/posix/eintr_wrapper.h"
-#include "base/task_scheduler/post_task.h"
+#include "base/task_runner_util.h"
+#include "base/threading/worker_pool.h"
 #include "base/time/default_tick_clock.h"
 #include "net/base/address_list.h"
 #include "net/base/io_buffer.h"
 #include "net/base/ip_endpoint.h"
 #include "net/base/net_errors.h"
 #include "net/base/network_activity_monitor.h"
 #include "net/base/network_change_notifier.h"
 #include "net/base/sockaddr_storage.h"
 #include "net/log/net_log.h"
 #include "net/log/net_log_event_type.h"
@@ skipping 96 matching lines @@
 }
 
 bool IsTCPFastOpenUserEnabled() {
   return g_tcp_fastopen_user_enabled;
 }
 
 // This is asynchronous because it needs to do file IO, and it isn't allowed to
 // do that on the IO thread.
 void CheckSupportAndMaybeEnableTCPFastOpen(bool user_enabled) {
 #if defined(OS_LINUX) || defined(OS_ANDROID)
-  base::PostTaskWithTraitsAndReplyWithResult(
-      FROM_HERE, base::TaskTraits().MayBlock().WithShutdownBehavior(
-                     base::TaskShutdownBehavior::CONTINUE_ON_SHUTDOWN),
+  base::PostTaskAndReplyWithResult(
+      base::WorkerPool::GetTaskRunner(/*task_is_slow=*/false).get(),
+      FROM_HERE,
       base::Bind(SystemSupportsTCPFastOpen),
       base::Bind(RegisterTCPFastOpenIntentAndSupport, user_enabled));
 #endif
 }
 
 TCPSocketPosix::TCPSocketPosix(
     std::unique_ptr<SocketPerformanceWatcher> socket_performance_watcher,
     NetLog* net_log,
     const NetLogSource& source)
     : socket_performance_watcher_(std::move(socket_performance_watcher)),
@@ skipping 662 matching lines @@
     if (info.tcpi_rtt > 0) {
       *out_rtt = base::TimeDelta::FromMicroseconds(info.tcpi_rtt);
       return true;
     }
   }
 #endif  // defined(TCP_INFO)
   return false;
 }
 
 }  // namespace net