Fix test so it doesn't try to build Everything::TestObj twice.
Fix test so it doesn't try to build Everything::TestObj twice.

Premature undef'ing of method_missing broke GirFFI's check to avoid double
setup.

jcupitt/gir_ffi,mvz/gir_ffi,mvz/gir_ffi,jcupitt/gir_ffi,mvz/gir_ffi