Add missing #include around sequenced_worker_pool.h in //chrome

chrome/browser/component_updater/ev_whitelist_component_installer.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/component_updater/ev_whitelist_component_installer.h"
 
 #include <memory>
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/path_service.h"
+#include "base/threading/sequenced_worker_pool.h"
 #include "base/version.h"
 #include "components/component_updater/component_updater_paths.h"
 #include "components/packed_ct_ev_whitelist/packed_ct_ev_whitelist.h"
 #include "content/public/browser/browser_thread.h"
 
 using component_updater::ComponentUpdateService;
 
 namespace {
 const base::FilePath::CharType kCompressedEVWhitelistFileName[] =
     FILE_PATH_LITERAL("ev_hashes_whitelist.bin");
@@ skipping 126 matching lines @@
   DefaultComponentInstaller* installer =
       new DefaultComponentInstaller(std::move(traits));
   installer->Register(cus, base::Closure());
 
   content::BrowserThread::PostAfterStartupTask(
       FROM_HERE, content::BrowserThread::GetBlockingPool(),
       base::Bind(&DeleteWhitelistCopy, user_data_dir));
 }
 
 }  // namespace component_updater