Remove unused include in sequenced_worker_pool.h

blimp/client/core/session/assignment_source.cc

 // Copyright 2016 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 "blimp/client/core/session/assignment_source.h"
 
 #include <memory>
 #include <utility>
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "base/command_line.h"
 #include "base/files/file_util.h"
 #include "base/json/json_reader.h"
 #include "base/json/json_writer.h"
 #include "base/location.h"
 #include "base/memory/ref_counted.h"
 #include "base/numerics/safe_conversions.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/task_runner_util.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/values.h"
 #include "blimp/client/core/switches/blimp_client_switches.h"
 #include "blimp/common/get_client_auth_token.h"
 #include "blimp/common/protocol_version.h"
 #include "components/safe_json/safe_json_parser.h"
 #include "net/base/ip_address.h"
 #include "net/base/ip_endpoint.h"
@@ skipping 345 matching lines @@
 }
 
 void AssignmentSource::OnJsonParseError(const std::string& error) {
   DLOG(ERROR) << "Error while parsing assigner JSON: " << error;
   base::ResetAndReturn(&callback_)
       .Run(ASSIGNMENT_REQUEST_RESULT_BAD_RESPONSE, Assignment());
 }
 
 }  // namespace client
 }  // namespace blimp