Villager inventory full but still picks up weed..

My automatic weed farm stopped working. (Figured in some way an update might have reset the farmers inventory hence he has enough food so he won't farm much anymore.

So I put him in a minecart send him off to the zombie farm, got him turned, played zombie doctor, before putting him back in the farm, made sure to fill his inventory with 8 stacks of seeds, offered him some more stacks he didn't pick up.. so should be full right. Presto, should work..

NO, he starts farming but picks up the WEED??!!

Turned him another 4 times, each time same result.

Anything changed in update so he can ALWAYS pick up food even when having a full inventory of non consumables (like seeds)