fix. Pass args.force to _sync in revert method.

Change-Id: I67c3ef8c08a5294b1b2d61b4594bfb0bddc91c76
fix. Ensure lock file is created in revert..

Change-Id: I14cd90347a2fbb7103677d6912f33ef223ee442e
fix. No need to remove lock in revert, done in _sync call.

Change-Id: I5f5d8f51036002713b44afb8edc1e33141c38074