Ranked afk forgiveness

i was wining a ranked game but at about 20 minis the nami afks and we tried to hold our own and we held on for more than 15 mins but due to the fact that she afk'ed we lost the game because of that I would like to suggest that riot make a afk forgiveness so that when a ally afkes it wont affect ur lp. a lot of other moba's already do this. ex: vaingolory and it worked out well for them. i think riot should think about adding this too.