The enum for the planes is called gdl_plant_id_t. https://bugzilla.gnome.org/show_bug.cgi?id=655355
We weren't defining CLUTTER_CEX100_LIBGDL_PREFIX in the configure.ac and thus failing to compile when selecting the EGL/GDL winsys. Take the opportunity to rename that to COGL_CEX100_LIBGDL_PREFIX https://bugzilla.gnome.org/show_bug.cgi?id=655355