bug#23604: desktop-restore-in-current-display should default to t

[Drew Adams]

> I was talking only about the default value.  Please stop
> putting your words into my mouth.

Hm.  Sorry if I misunderstood you.  But these were your words:

  Can you explain why using display that is not the current
  one even makes sense?

Anyway, great.  Glad to hear it, if you're not claiming that
using a display other than the current makes no sense.

So the problems we see now with nil, once taken care of (bug
#20247), should have no bearing on which value to choose as
the default.

Which is what I said: let's see what happens with bug #20247,
and then decide which value is more useful as the default.

(Until then t is more useful, of course - that's this
workaround, #23604.)