This branch isn't even reached if `_ASTROPY_SETUP_ == True`.  In https://github.com/astropy/astropy/pull/867/files#L5R567 I changed the astropy.cfg generation to still behave as though it's running in "SETUP" mode (which really, it is).  But that's what also necessitated changes like https://github.com/astropy/astropy/pull/867/files#L3R15.  Now when the generate_config runs, those imports will *succeed*.  They're always attempted, but only allowed to fail if not in "SETUP" mode (where it's possible for them to fail if the extension modules haven't been built yet).