Remove duplicate `map_fmap_empty` of `fmap_empty`, and rename...
Remove duplicate map_fmap_empty
of fmap_empty
, and rename map_fmap_empty_inv
into fmap_empty_inv
for consistency's sake.
Remove duplicate map_fmap_empty
of fmap_empty
, and rename map_fmap_empty_inv
into fmap_empty_inv
for consistency's sake.