Comment 9 for bug 1587555

Turns out this is breaking in ubiquity because we don't get initscripts installed on the rootfs (since procps now depends on init-system-helpers instead).

For d-i installs this doesn't exactly break, but it's still a good idea to check for the file to exist before we try to modify it. Looks like in the d-i case, some other script may be creating an empty file before clock-setup runs.

On ubiquity, no such empty file is created, and we use a "copy" of 10clock-setup; so there needs to be an update to both packages.