On X11 when we send an XResizeWindow request to the X server it is happy
to say it is done when the request has been handed over to the window
manager. The window manager itself may however take some time to
actually do the resize. Godot expects that a resize request is
immediate. To work around this issue we could implement the whole
_NET_WM_SYNC_REQUEST protocol. However this protocol does not fit very
well with the way we currently process X events and would when
implemented in the current framework still cause a 1 frame delay between
a resize request and the actual resize happening.
This fixes#21720
9a1deedb84