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

chrome/browser/web_applications/web_app_win.cc

 // Copyright (c) 2012 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/web_applications/web_app_win.h"
 
 #include <shlobj.h>
 #include <stddef.h>
 
 #include <memory>
 
 #include "base/command_line.h"
 #include "base/files/file_enumerator.h"
 #include "base/files/file_util.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/md5.h"
 #include "base/path_service.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_piece.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/threading/sequenced_worker_pool.h"
 #include "base/win/shortcut.h"
 #include "base/win/windows_version.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/shell_integration_win.h"
 #include "chrome/browser/web_applications/update_shortcut_worker_win.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/installer/util/browser_distribution.h"
 #include "chrome/installer/util/shell_util.h"
 #include "chrome/installer/util/util_constants.h"
 #include "content/public/browser/browser_thread.h"
@@ skipping 584 matching lines @@
 
 }  // namespace internals
 
 void UpdateShortcutForTabContents(content::WebContents* web_contents) {
   // UpdateShortcutWorker will delete itself when it's done.
   UpdateShortcutWorker* worker = new UpdateShortcutWorker(web_contents);
   worker->Run();
 }
 
 }  // namespace web_app