Layout switching while button is pressed in 13.10

Question

In Saucy they added new utility to switch layouts, and i can't find there or in dconf Editor an option to switch languages while button is pressed. Is there any config file to add this option in it?

Answer 1

Still didn't find any answer, so i'm using Caps Lock button to switch layouts. One button lets make it faster than two. It's not ideal but may be a workaround.