I get the impression that they may stop laying if fed a diet of ONLY fruit. Not enough protein to make eggs.
But for most of us who feed layer pellets or other food that meets their protein requirements, feeding some fruit on the side won't hurt a thing!!!
When the roma tomatoes we put on pizzas at work get "out of date" or over ripe, the boss gives them to me for the chickens. They will eat just about anything we put on pizzas, so I get scraps for them all the time when we clean stuff out, but leftover tomatoes are probably their favorite!