bug#17768: 24.3; problem with two ruler-mode windows

[Stefan Monnier]

>> This means that we shouldn't provide `posn-col-row' in the first place
>> which I'd consider the best solution.
> I see no reason to delete well established APIs, just because Emacs
> overgrew the time when they were named.

We could consider obsoleting the function if we thing that its use is
either less convenient than alternatives, or tends to lead to bugs which
don't affect the alternative.

I don't know enough posn-col-row's uses to judge.


        Stefan