Reland of move header dependencies from sequence_checker.h to sequenced_worker_pool.h

chrome/browser/chromeos/file_manager/snapshot_manager.cc

 // Copyright 2014 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/file_manager/snapshot_manager.h"
 
 #include "base/bind.h"
 #include "base/sys_info.h"
+#include "base/threading/sequenced_worker_pool.h"
 #include "chrome/browser/chromeos/file_manager/app_id.h"
 #include "chrome/browser/chromeos/file_manager/fileapi_util.h"
 #include "chrome/browser/profiles/profile.h"
 #include "content/public/browser/browser_thread.h"
 #include "google_apis/drive/task_util.h"
 #include "storage/browser/blob/shareable_file_reference.h"
 #include "storage/browser/fileapi/file_system_context.h"
 #include "third_party/cros_system_api/constants/cryptohome.h"
 
 namespace file_manager {
@@ skipping 186 matching lines @@
   if (result != base::File::FILE_OK) {
     callback.Run(base::FilePath());
     return;
   }
 
   file_refs_.push_back(FileReferenceWithSizeInfo(file_ref, file_info.size));
   callback.Run(platform_path);
 }
 
 }  // namespace file_manager