FileStoreBackup and FileStoreRestore are currently broken as a side effect of the fix from
OAK-3348. (FileStoreBackupTest is currently being skipped).
In oak-segment backup and restore functionality relied on the Compactor class. The latter is gone in oak-segment-next as it is not needed for online compaction any more.
Instead of sharing functionality from compaction directly, I think backup and restore should come up with its own implementation that could be individually tweaked for its task. If there is commonalities with offline compaction those can still be shared thorough a common base class. See