Prepare coleslaw according to recipe.
In a large slow cooker, combine chicken and root beer. Cook on low for 3 to 4 hours, until chicken is cooked through and extremely tender.
Transfer chicken to a large bowl. Using two forks, shred chicken. Drain root beer and discard, then return chicken to slow cooker.
Stir in barbecue sauce. Cook on low for 1 hour. Season with salt and pepper.
Slice King's Hawaiian Original Hawaiian Sweet Dinner Rolls in half horizontally. Divide shredded chicken between bottom buns, then top with a generous scoop of coleslaw and a pickle.