Always use TaskScheduler::InitParams to initialize a TaskScheduler.

base/task_scheduler/scheduler_worker_pool_impl.cc

Index: base/task_scheduler/scheduler_worker_pool_impl.cc
diff --git a/base/task_scheduler/scheduler_worker_pool_impl.cc b/base/task_scheduler/scheduler_worker_pool_impl.cc
index d45495413ff95194b3fd90e2fb803e1e825896fd..ad118afe3152a97fc5fc93e81c7573a4915c6613 100644
--- a/base/task_scheduler/scheduler_worker_pool_impl.cc
+++ b/base/task_scheduler/scheduler_worker_pool_impl.cc
@@ -265,7 +265,7 @@ void SchedulerWorkerPoolImpl::Start(const SchedulerWorkerPoolParams& params) {
     // highest index is at the bottom of the idle stack.
     for (int index = params.max_threads() - 1; index >= 0; --index) {
       workers_[index] = make_scoped_refptr(new SchedulerWorker(
-          params.priority_hint(),
+          priority_hint_,
           MakeUnique<SchedulerWorkerDelegateImpl>(
               this, re_enqueue_sequence_callback_, index),
           task_tracker_, params.backward_compatibility(),