Revert of Remove header dependencies from sequence_checker.h to sequenced_worker_pool.h

chrome/browser/chromeos/accessibility/accessibility_highlight_manager_interactive_uitest.cc

 // Copyright (c) 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 "chrome/browser/chromeos/accessibility/accessibility_highlight_manager.h"
 
 #include "ash/shell.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/run_loop.h"
-#include "base/threading/sequenced_worker_pool.h"
 #include "chrome/browser/chromeos/ui/accessibility_focus_ring_controller.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "chromeos/chromeos_switches.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/focused_node_details.h"
 #include "content/public/browser/notification_types.h"
 #include "ui/aura/window.h"
 #include "ui/base/ime/dummy_text_input_client.h"
 #include "ui/base/ime/input_method.h"
 #include "ui/base/ime/text_input_client.h"
@@ skipping 208 matching lines @@
   // This is a smoke test to assert that something is drawn in the right
   // part of the screen of approximately the right size and color.
   // There's deliberately some tolerance for tiny errors.
   EXPECT_NEAR(1608, diff_count(), 50);
   EXPECT_NEAR(255, SkColorGetR(average_diff_color()), 5);
   EXPECT_NEAR(201, SkColorGetG(average_diff_color()), 5);
   EXPECT_NEAR(152, SkColorGetB(average_diff_color()), 5);
 }
 
 }  // namespace chromeos