Revert "ui.backend.gtk: try yield in idle callback."
Revert "ui.backend.gtk: try yield in idle callback."

This reverts commit 2929cc21f5d1b17e71014f0c32f3fb2f33f744b6.

bjourne/factor,tgunr/factor,bpollack/factor,nicolas-p/factor,AlexIljin/factor,factor/factor,AlexIljin/factor,factor/factor,mrjbq7/factor,AlexIljin/factor,bjourne/factor,bpollack/factor,tgunr/factor,mrjbq7/factor,bjourne/factor,nicolas-p/factor,factor/factor,factor/factor,AlexIljin/factor,factor/factor,bjourne/factor,AlexIljin/factor,mrjbq7/factor,bpollack/factor,bpollack/factor,bpollack/factor,factor/factor,tgunr/factor,AlexIljin/factor,bjourne/factor,mrjbq7/factor,bpollack/factor,nicolas-p/factor,mrjbq7/factor,tgunr/factor,AlexIljin/factor,nicolas-p/factor,nicolas-p/factor,bpollack/factor,mrjbq7/factor,bjourne/factor,tgunr/factor,tgunr/factor,nicolas-p/factor,bjourne/factor,nicolas-p/factor