histedit: use repo.revs() instead of repo.set() where revisions are needed Follows up 72da480db4a5. This is just a micro optimization, but looks slightly nicer.

acl: replace bare getpass.getuser() by platform function Follows up dbadf28d4db0. bytestr() shouldn't be applied here because getuser() isn't guaranteed to be all in ASCII. This change means GetUserNameA() is used on Windows, but that's probably better than trying to get the current user name in UNIX way.