bug#25818: 25.2; frame moved off display does not return (OS X)

[martin rudalics]

> I fixed the patch so that child frames are never constrained (after
> some testing, it seems that a child frame cannot get stuck off screen
> as long as its parent is still visible).  To test this out, evaluate
> the following from emacs -Q,
>
> (progn
>    (setq test-frame (make-frame `((parent-frame . ,(selected-frame)))))
>    (set-frame-position test-frame 0 500))
>
> and drag the parent frame down until its child is off screen.

Does this mean that the child frame does _not_ move together with its
parent frame?  That would constitute a major deviation from the other
platforms.

martin