Move EXPECT_DCHECK_DEATH from base/task_scheduler and use it in relevant base/ tests

base/task_scheduler/priority_queue_unittest.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 "base/task_scheduler/priority_queue.h"
 
 #include <memory>
 
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/task_scheduler/sequence.h"
 #include "base/task_scheduler/task.h"
 #include "base/task_scheduler/task_traits.h"
-#include "base/task_scheduler/test_utils.h"
+#include "base/test/gtest_util.h"
 #include "base/threading/platform_thread.h"
 #include "base/threading/simple_thread.h"
 #include "base/time/time.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace base {
 namespace internal {
 
 namespace {
 
@@ skipping 149 matching lines @@
 
   // End the Transaction on the current thread.
   transaction.reset();
 
   // The other thread should exit after its call to BeginTransaction() returns.
   thread_beginning_transaction.Join();
 }
 
 }  // namespace internal
 }  // namespace base