Fix geometryRestore() handling with maximize quick tile mode

geometryRestore() is no longer updated after mapping the window, so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