BNSF filed a petition for permissive appeal, which we granted. See BNSF Ry. Co. v. Baca, No. 02-17-00168-CV, 2017 WL 2570826, at *1 (Tex. App.—Fort Worth June 14, 2017, no pet.) (mem. op. & order). The controlling question of law the trial court identified and ruled upon in its order, and the sole issue in this appeal, is