ReplicatedPG: Fix oi.size bug in _rollback_to
ReplicatedPG: Fix oi.size bug in _rollback_to

_rollback_to calls _delete_head before cloning the clone into place.
_delete_head sets the object info size to 0.  _rollback_to now resets
the size to match the rolled back object.  Previously, this bug
manifested as a failed assert in scrub when checking the object sizes.

Signed-off-by: Samuel Just <080670f7d9c6f3eb64055fc3fc7c93ba2c444c40@hq.newdream.net>

ajnelson/ceph,ajnelson/ceph,ajnelson/ceph,ajnelson/ceph,ajnelson/ceph,ajnelson/ceph