Automated IWYU fix for TaskRunner includes.

components/ntp_snippets/remote/remote_suggestions_provider_impl_unittest.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 "components/ntp_snippets/remote/remote_suggestions_provider_impl.h"
 
 #include <memory>
 #include <utility>
 #include <vector>
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/json/json_reader.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/test/histogram_tester.h"
 #include "base/test/simple_test_clock.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/time/default_clock.h"
 #include "base/time/time.h"
 #include "components/image_fetcher/core/image_decoder.h"
 #include "components/image_fetcher/core/image_fetcher.h"
@@ skipping 1876 matching lines @@
   WaitForSuggestionsProviderInitialization(service.get(),
                                            /*set_empty_response=*/true);
 
   // The scheduler should be notified of clearing the history.
   EXPECT_CALL(*scheduler(), OnSuggestionsCleared());
   service->OnStatusChanged(RemoteSuggestionsStatus::ENABLED_AND_SIGNED_OUT,
                            RemoteSuggestionsStatus::ENABLED_AND_SIGNED_IN);
 }
 
 }  // namespace ntp_snippets