Fix to lose a focus when move the focus from the delayed focus-in/out.
Fix to lose a focus when move the focus from the delayed focus-in/out.

Some applications likes google-chrome URL entry could have the delayed
focus-in and focus-out events and ibus fails to get the new focus.

BUG=rhbz#919863, rhbz#1136623

Review URL: https://codereview.appspot.com/7725045

Keruspe/ibus,ibus/ibus,fujiwarat/ibus,Keruspe/ibus,ibus/ibus,j717273419/ibus,Keruspe/ibus,fujiwarat/ibus,fujiwarat/ibus,ibus/ibus,j717273419/ibus,j717273419/ibus,j717273419/ibus,fujiwarat/ibus,ibus/ibus,Keruspe/ibus