[cairo] [Win32] Why does Win32 surface return NULL for invalid format?

[Kouhei Sutou]

Hi,

cairo_win32_surface_create_with_ddb() returns NULL when
passed format is not CAIRO_FORMAT_RGB24. I think
cairo_win32_surface_create_with_ddb() should return nil
surface that has CAIRO_STATUS_INVALID_FORMAT status like
cairo_image_surface_create().


Thanks,
--
kou