Comment 18 for bug 1273764

@psusi, Please look in /etc/grub.d/30_os-prober. In particular, the last line reads:

> adjust_timeout

And the definition of `adjust_timeout` is:

> adjust_timeout () {
> if [ "$quick_boot" = 1 ] && [ "x${found_other_os}" != "x" ]; then
> cat << EOF
> set timeout_style=menu
> if [ "\${timeout}" = 0 ]; then
> set timeout=10
> fi
> EOF
> fi
> }

As you can see the `timeout` variable is set/reset to 10 (seconds).