Revert of Rollback option put behind the flag. (https://codereview.chromium.org/
267393011/)
Reason for revert:
This seems to have broken ResetFirstAfterBootTest.SuccessOnRollbackRequested on http://build.chromium.org/p/chromium.chromiumos/builders/Linux%20ChromiumOS%20Tests%20%282%29/builds/23801.
Original issue's description:
> Rollback option put behind the flag.
>
> BUG=368860
>
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=269753
TBR=nkostylev@chromium.org,merkulova@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=368860
Review URL: https://codereview.chromium.org/
279203002
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@269762 0039d316-1c4b-4281-b951-d872f2087c98