bug#19988: 25.0.50; Drag events ending in different frame

[martin rudalics]

> Ok.  I think that would still be a nice enhancement although not
> pressing.

It's tricky as I explained earlier.  Emacs knows about the x/y-extents
of its visible frames but has no idea about the Z order they appear in.
So if you have two overlapping target frames, how would it know which
one to choose?

> At least your rewrite of my function isn't really obvious to
> me and probably most users.

Basically you should rewrite you function using mouse tracking.  Mine is
only a hack to work within the frame of what you wrote before.

> And it also behaves wrongly in some
> situations with overlapping frames.

Expected.  See above.

martin