Use TaskScheduler instead of blocking pool in device_commands_factory_chromeos.cc.

The blocking pool is being deprecated in favor of TaskScheduler.

BUG=667892
R=bartfab@chromium.org

Review-Url: https://codereview.chromium.org/2837083002
Cr-Commit-Position: refs/heads/master@{#467729}

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

@@ -7,7 +7,7 @@
 #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"
@@ -16,7 +16,6 @@
 #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;
 
@@ -37,9 +36,12 @@ DeviceCommandsFactoryChromeOS::BuildJobForType(em::RemoteCommand_Type type) {
     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)
+                      .WithShutdownBehavior(
+                          base::TaskShutdownBehavior::SKIP_ON_SHUTDOWN)))));
     case em::RemoteCommand_Type_DEVICE_SET_VOLUME:
       return base::WrapUnique<RemoteCommandJob>(
           new DeviceCommandSetVolumeJob());