bug#64423: 29.0.92; save-interprogram-paste-before-kill doesn't prevent streaming large selections

[Spencer Baugh]

FYI, just for completeness and to help future users, I managed to track
down the original source of this "large selection" for me, which was
causing gui-get-selection to hang.  It's this bug in xrdp when an image
is copied:

https://github.com/neutrinolabs/xrdp/issues/2763

This actually is just a hang with no data, not a large selection.  So in
the end, preventing the streaming of large selections wouldn't have
helped.

The patch that we did end up applying, to ignore quit in
gui-get-selection in kill-new, works great at mitigating this xrdp bug
though.