[tz] time and cost to reprogram computers for DST in Japan

[Florian Weimer]

* Tom Lane:

> I rather imagine the professor has a point.  Yeah, code that uses tzdb
> would be easy to update.  But Japan is likely chock-full of locally
> grown code that has never had to cope with any situation other than
> "JST = UTC+9", and probably hasn't got any generality whatsoever
> about its timestamp handling.

At last some of this code has to be touched for the new era name
anyway, and *that* work is supposed to complete within a few months.
(The last era transition was in 1989.)