Revert of Disallow posting tasks to SequencedWorkerPools by default.

base/test/launcher/test_launcher.cc

 // Copyright 2013 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 "base/test/launcher/test_launcher.h"
 
 #include <memory>
 
 #include "base/at_exit.h"
 #include "base/bind.h"
@@ skipping 20 matching lines @@
 #include "base/strings/string_util.h"
 #include "base/strings/stringize_macros.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/test/gtest_util.h"
 #include "base/test/launcher/test_launcher_tracer.h"
 #include "base/test/launcher/test_results_tracker.h"
 #include "base/test/sequenced_worker_pool_owner.h"
 #include "base/test/test_switches.h"
 #include "base/test/test_timeouts.h"
-#include "base/threading/sequenced_worker_pool.h"
 #include "base/threading/thread.h"
 #include "base/threading/thread_checker.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/time/time.h"
 #include "build/build_config.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_POSIX)
 #include <fcntl.h>
 
@@ skipping 761 matching lines @@
     parallel_jobs_ = jobs;
   } else if (command_line->HasSwitch(kGTestFilterFlag) && !BotModeEnabled()) {
     // Do not run jobs in parallel by default if we are running a subset of
     // the tests and if bot mode is off.
     parallel_jobs_ = 1U;
   }
 
   fprintf(stdout, "Using %" PRIuS " parallel jobs.\n", parallel_jobs_);
   fflush(stdout);
   if (parallel_jobs_ > 1U) {
-    // Allow usage of SequencedWorkerPool to launch test processes.
-    // TODO(fdoray): Remove this once the SequencedWorkerPool to TaskScheduler
-    // redirection experiment concludes https://crbug.com/622400.
-    SequencedWorkerPool::EnableForProcess();
-
     worker_pool_owner_ = MakeUnique<SequencedWorkerPoolOwner>(
         parallel_jobs_, "test_launcher");
   } else {
     worker_thread_ = MakeUnique<Thread>("test_launcher");
     worker_thread_->Start();
   }
 
   if (command_line->HasSwitch(switches::kTestLauncherFilterFile) &&
       command_line->HasSwitch(kGTestFilterFlag)) {
     LOG(ERROR) << "Only one of --test-launcher-filter-file and --gtest_filter "
@@ skipping 336 matching lines @@
   }
 
   std::string snippet(full_output.substr(run_pos));
   if (end_pos != std::string::npos)
     snippet = full_output.substr(run_pos, end_pos - run_pos);
 
   return snippet;
 }
 
 }  // namespace base