Currently we have the bump guarded by an env variable:

https://github.com/openshift/cluster-etcd-operator/blob/master/bindata/etcd/cluster-restore.sh#L151-L155

and a hardcode with 1bn revision numbers in:

https://github.com/openshift/cluster-etcd-operator/blob/master/bindata/etcd/restore-pod.yaml#L64-L68

With this story we should remove the feature flag and enable the bumping by default. The bump amount should come from the file created in ETCD-652 plus some slack percentage. If the file doesn't exist we assume the default value of a billion again.