Bug#759737: debian-installer: Need preseed entry to select default grub device

[Chris Kuehl <ckuehl@ocf.berkeley.edu>]

Hi all,

Andrew's patch looks very reasonable to me, as it would allow sysadmins
to fully automate installs without further complicating the issues
raised in #712907 (which mostly affect interactive installs).

I've spent a few hours attempting to test the patch, but can't seem to
properly integrate my locally-built grub-installer udeb into a netboot
build (either via localudebs or by downloading and unpacking the udeb
manually from the installer shell). I strongly suspect my own
incompetence is to blame, though, and not the patch.

I might be missing something, but we can't seem to find any other way to
fully automate jessie installs via preseeding, like we could with
wheezy. (For context, our physical machines are split between using
/dev/sda and /dev/sde for the first hard drive, while VirtualBox uses
/dev/sda and KVM /dev/vda.)

I wonder whether the severity of this bug should be raised to important?
I suspect that automating installs is an important feature for many
other d-i users, so I'm not sure wishlist is appropriate for this bug.

I'm going to continue attempting to test the patch, and report back if I
have any luck.

Many thanks!
Chris