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

chrome/browser/download/download_commands.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/download/download_commands.h"
 
 #include <stdint.h>
 
 #include "base/base64.h"
 #include "base/files/file_util.h"
 #include "base/macros.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/threading/sequenced_worker_pool.h"
 #include "build/build_config.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/download/download_crx_util.h"
 #include "chrome/browser/download/download_item_model.h"
 #include "chrome/browser/download/download_prefs.h"
 #include "chrome/browser/image_decoder.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/safe_browsing/download_protection_service.h"
 #include "chrome/browser/safe_browsing/safe_browsing_service.h"
 #include "chrome/browser/ui/browser_finder.h"
@@ skipping 378 matching lines @@
       download_item_->GetReceivedBytes() > kMaxImageClipboardSize) {
     return;
   }
 
   if (!DownloadItemModel(download_item_).HasSupportedImageMimeType())
     return;
 
   base::FilePath file_path = download_item_->GetFullPath();
   ImageClipboardCopyManager::Start(file_path);
 }