If the OP travels with carry on luggage only, he will deplane and take his luggage through security. Then he will be at the departure gates. It will not have any significant effect on the time it takes him to get from plane to gate.

Unless he intends to purchase a bottle of liquid en-route to NRT, I can't think of a reason to check bags as far as NRT, and collect them, take them through customs, and re-check them. That's a real edge case.