Add TaskPriority as a parameter to SequencedWorkerPool in preparation for TaskScheduler experiment.

base/test/sequenced_worker_pool_owner.cc

Index: base/test/sequenced_worker_pool_owner.cc
diff --git a/base/test/sequenced_worker_pool_owner.cc b/base/test/sequenced_worker_pool_owner.cc
index 37bad2b29d25c5e5084cd9e6c69ec87da416d45a..fe4c7ed363b8c43b8c8d5c5f295f59e3d2e517b2 100644
--- a/base/test/sequenced_worker_pool_owner.cc
+++ b/base/test/sequenced_worker_pool_owner.cc
@@ -14,7 +14,10 @@ SequencedWorkerPoolOwner::SequencedWorkerPoolOwner(
     size_t max_threads,
     const std::string& thread_name_prefix)
     : constructor_message_loop_(MessageLoop::current()),
-      pool_(new SequencedWorkerPool(max_threads, thread_name_prefix, this)),
+      pool_(new SequencedWorkerPool(max_threads,
+                                    thread_name_prefix,
+                                    TaskPriority::USER_VISIBLE,
+                                    this)),
       has_work_call_count_(0) {}
 
 SequencedWorkerPoolOwner::~SequencedWorkerPoolOwner() {