Create a XlibSurface from a existing cairo_surface_t*. XlibSurface is a garbage collected class. It will call cairo_surface_destroy when it gets collected by the GC or when dispose() is called.

Warning: ptr's reference count is not increased by this function! Adjust reference count before calling it if necessary

Only use this if you know what your doing! This function should not be needed for standard cairoD usage.