update_engine: Place enterprise rollback save marker file
- There are now two types of rollback. One that does a full powerwash
and one that save some system state.
- When an enterprise rollback powerwash is scheduled, place a marker
file to tell the shutdown process to save data before rebooting.
- This lets rollback preserve additional data over a powerwash that
can be restored later.
- Change a few places that were using is_rollback to save_rollback_data
to be explicit.
BUG=chromium:955463
TEST=unittests
Change-Id: I9f18319e711e425a6e712dd319e03bcc6ddd0a1b
Reviewed-on: https://chromium-review.googlesource.com/1414030
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: Zentaro Kavanagh <zentaro@chromium.org>
Reviewed-by: Amin Hassani <ahassani@chromium.org>
18 files changed