Add header required for cros build

components/feedback/feedback_uploader.h

 // 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.
 
 #ifndef COMPONENTS_FEEDBACK_FEEDBACK_UPLOADER_H_
 #define COMPONENTS_FEEDBACK_FEEDBACK_UPLOADER_H_
 
 #include <queue>
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/file_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
+#include "base/threading/sequenced_worker_pool.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
 
 namespace feedback {
 
 typedef base::Callback<void(const std::string&)> ReportDataCallback;
 
 class FeedbackReport;
 
 // FeedbackUploader is used to add a feedback report to the queue of reports
@@ skipping 51 matching lines @@
   base::TimeDelta retry_delay_;
   std::string url_;
   base::SequencedWorkerPool* pool_;
 
   DISALLOW_COPY_AND_ASSIGN(FeedbackUploader);
 };
 
 }  // namespace feedback
 
 #endif  // COMPONENTS_FEEDBACK_FEEDBACK_UPLOADER_H_