bug#14575: 24.3.50.1; Overlays with a window property affect other windows

[Eli Zaretskii]

> Date: Sat, 8 Jun 2013 19:47:24 +0100
> From: E Sabof <esabof@gmail.com>
> Cc: 14575-done@debbugs.gnu.org
> 
> Cool, thanks. That was fast.

Well, it's Saturday...

Btw, this bug was introduced 2 years ago, during the development of
v24.1, and no one ever said anything until now.  I guess that speaks
volumes of how frequently people use window-specific overlays.