On second thought, how about if we install update-game-score only when 
the builder specifies the game user or group. This will let Gentoo roll 
along much as before, while simplifying installation for distributions 
that don't support or bother to configure a game user or group. Although 
this doesn't simplify the Emacs source as much as the previously 
proposed patch, it's still better than what we have now. Proposed patch 
attached.