Modify the autoupdater to reset the stateful update state on AU failure.

This change modifies the updater to reset the stateful update state
if an AU fails.  This is needed so that we don't incorrectly continue
with a stateful update even when the rootfs fails to update.

CQ-DEPEND=I3dd6a29b087587c7557fa5a7968ebd48a52dd263
BUG=chromium-os:30795
TEST=Tested with local devserver and the rootfs update failing with
change I5afb4eb74a943a62a8c1e2cc5365d0a910d63051

Change-Id: I28b6b471ad5a05b6650ffd2608927ac8aa3bfd16
Reviewed-on: https://gerrit.chromium.org/gerrit/23304
Reviewed-by: Chris Masone <cmasone@chromium.org>
Commit-Ready: Chris Sosa <sosa@chromium.org>
Tested-by: Chris Sosa <sosa@chromium.org>
1 file changed