Show warning message if sideload failed or is interrupted.

For non A/B and Virtual A/B devices where sideloading may affect
the existing OS,
- If sideload has failed, show a warning message in recovery menu header.
- If sideload has interrupted, automatically reboot back into recovery and
  show the warning message in recovery menu header.

Test: the above
Fixes: 140749209
Change-Id: Ifdfc28b45975cdc31b6fce2ecb99acc31bc61fa8