Use TaskScheduler instead of blocking pool in device_commands_factory_chromeos.cc.

chrome/browser/chromeos/policy/remote_commands/device_commands_factory_chromeos.cc

 // Copyright 2015 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/chromeos/policy/remote_commands/device_commands_factory_chromeos.h"
 
 #include <memory>
 
 #include "base/memory/ptr_util.h"
-#include "base/threading/sequenced_worker_pool.h"
+#include "base/task_scheduler/post_task.h"
 #include "chrome/browser/chromeos/policy/remote_commands/device_command_fetch_status_job.h"
 #include "chrome/browser/chromeos/policy/remote_commands/device_command_reboot_job.h"
 #include "chrome/browser/chromeos/policy/remote_commands/device_command_screenshot_job.h"
 #include "chrome/browser/chromeos/policy/remote_commands/device_command_set_volume_job.h"
 #include "chrome/browser/chromeos/policy/remote_commands/screenshot_delegate.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "components/policy/core/common/remote_commands/remote_command_job.h"
 #include "components/policy/proto/device_management_backend.pb.h"
-#include "content/public/browser/browser_thread.h"
 
 namespace em = enterprise_management;
 
 namespace policy {
 
 DeviceCommandsFactoryChromeOS::DeviceCommandsFactoryChromeOS() {
 }
 
 DeviceCommandsFactoryChromeOS::~DeviceCommandsFactoryChromeOS() {
 }
 
 std::unique_ptr<RemoteCommandJob>
 DeviceCommandsFactoryChromeOS::BuildJobForType(em::RemoteCommand_Type type) {
   switch (type) {
     case em::RemoteCommand_Type_DEVICE_REBOOT:
       return base::WrapUnique<RemoteCommandJob>(new DeviceCommandRebootJob(
           chromeos::DBusThreadManager::Get()->GetPowerManagerClient()));
     case em::RemoteCommand_Type_DEVICE_SCREENSHOT:
       return base::WrapUnique<RemoteCommandJob>(
           new DeviceCommandScreenshotJob(base::MakeUnique<ScreenshotDelegate>(
-              content::BrowserThread::GetBlockingPool()->GetSequencedTaskRunner(
-                  content::BrowserThread::GetBlockingPool()
-                      ->GetSequenceToken()))));
+              base::CreateSequencedTaskRunnerWithTraits(
+                  base::TaskTraits().MayBlock().WithPriority(
+                      base::TaskPriority::BACKGROUND)))));

[Thiemo Nagel, 2017/04/27 09:48:43]

Same here, I think we should SKIP_ON_SHUTDOWN.  I don't see value in blocking
shutdown on screenshotting.

[fdoray, 2017/04/27 13:27:45]

Done.

     case em::RemoteCommand_Type_DEVICE_SET_VOLUME:
       return base::WrapUnique<RemoteCommandJob>(
           new DeviceCommandSetVolumeJob());
     case em::RemoteCommand_Type_DEVICE_FETCH_STATUS:
       return base::WrapUnique<RemoteCommandJob>(
           new DeviceCommandFetchStatusJob());
     default:
       return nullptr;
   }
 }
 
 }  // namespace policy