emitter: Fix an oops that allowed 'if 1: return' within __main__.
emitter: Fix an oops that allowed 'if 1: return' within __main__.

This is another case of the wrong check being used by the emitter. It was only checking
for not being in __main__'s block, rather than checking for being inside a method.

boardwalk/lily,crasm/lily,crasm/lily,boardwalk/lily,crasm/lily