In some cases it can happen, that the order of input events and
window events is not followed, when input buffering or input accumulation
is active.
The display server order `InputEvent` => window-event gets changed to
window-event => `InputEvent` which becomes problematic in certain
situations.
This PR makes sure, that the order is adhered to by flushing input events
before a window event is sent.
Previously this problem was mitigated by discarding these delayed events.
But this solution was problematic in the setting of android input events.
945babc619