The previous upgrade hook didn't change all the perms on files in the host
distdir because the default value expands to a symlink which `find` did not
walk. Add the -H flag to make that happen.
For people who haven't upgraded yet, stub out the existing 38 hook.
BUG=chromium-os:3616
TEST=add a root owned file to host distdir, run ./update_chroot, see file owners fixed
Change-Id: I3f5f88b4fb1d27ce588a342331ad10e957961bcc
Reviewed-on: https://gerrit.chromium.org/gerrit/24459
Reviewed-by: Zdenek Behan <zbehan@chromium.org>
Commit-Ready: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
