Bug#888549: chrome-gnome-shell: Please don't use /etc/opt, it's not FHS-compliant

[Jeremy Bicha]

Control: severity -1 serious
Control: notfound -1 9-2
Control: found -1 10.1-3

I couldn't get this to work using a postrm script (the script appeared
to run at the wrong time), so maybe we need a trigger after all.

Thanks,
Jeremy Bicha