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

extensions/browser/content_verify_job.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 "extensions/browser/content_verify_job.h"
 
 #include <algorithm>
 
 #include "base/metrics/histogram_macros.h"
 #include "base/stl_util.h"
 #include "base/task_runner_util.h"
+#include "base/threading/sequenced_worker_pool.h"
 #include "base/timer/elapsed_timer.h"
 #include "content/public/browser/browser_thread.h"
 #include "crypto/secure_hash.h"
 #include "crypto/sha2.h"
 #include "extensions/browser/content_hash_reader.h"
 
 namespace extensions {
 
 namespace {
 
@@ skipping 191 matching lines @@
             << " reason:" << reason;
     failure_callback_.Run(reason);
     failure_callback_.Reset();
   }
   if (g_test_observer)
     g_test_observer->JobFinished(
         hash_reader_->extension_id(), hash_reader_->relative_path(), failed_);
 }
 
 }  // namespace extensions