Re-enable test_ghash_nested_everything_return.
Re-enable test_ghash_nested_everything_return.

Now that bug 581685 has been committed to g-object-introspection, we can
re-enable this test, added as part of bug 581695.

This reverts commit 047ff49ad9d06407a3ca0996a2f196875ba1c1f4.

magcius/gjs,joeshaw/gjs,pixunil/cjs,joeshaw/gjs,pixunil/cjs,mtwebster/cjs,pixunil/cjs,joeshaw/gjs,endlessm/gjs,mtwebster/cjs,endlessm/gjs,endlessm/gjs,mtwebster/cjs,endlessm/gjs,djdeath/gjs,magcius/gjs,djdeath/gjs,joeshaw/gjs,djdeath/gjs,djdeath/gjs,mtwebster/cjs,pixunil/cjs,mtwebster/cjs,djdeath/gjs,magcius/gjs,pixunil/cjs,endlessm/gjs,magcius/gjs,joeshaw/gjs,magcius/gjs