We have issues with correct resize sequence and happen to commit old-sized
buffers even after configure event for the new size has been already
acknowledged. While the reason for that stays unknown, let's at least
workaround the problem by faking window geometry into expected size.
This does not fix visual glitch on e.g. fullscreen toggling, but having
a split-second glitch is still a much better outcome than being
terminated by the compositor for protocol violation.