geometryRestore() is no longer updated after mapping the window, so
setQuickTileMode() has to update geometryRestore() explicitly to the
correct value.
With this change, geometryRestore() will be updated as follows:
* if the window is tiled, geometryRestore() is valid, nothing to do
* the window has been dragged to the top edge, set geometryRestore() to
the geometry that the window had when starting move
* otherwise, use the current move resize geometry