In a 5- to 6-quart slow cooker, combine the first six ingredients (through pepper). Top with potatoes, carrots, celery, and onion. Place chicken on top of the vegetables. Cover and cook on low 9 to 10 hours or on high 4 1/2 to 5 hours or until chicken is no longer pink (170°F) and vegetables are tender. Using a slotted spoon, remove chicken and vegetables to a platter. Drizzle with cooking liquid. Sprinkle with rosemary.