Bug#770596: gnome-terminal: leaves bash processes behind

[Egmont Koblinger]

The first upstream fix was incorrect.  The correct fix is these two commits
on top of each other:
https://git.gnome.org/browse/vte/commit/?h=vte-0-38&id=d9d83d4
https://git.gnome.org/browse/vte/commit/?h=vte-0-38&id=b033047