Investigate why a null FileLock is declared but not used

It is not assigned but later on it is checked for null and if not then released:
https://github.com/jbosstm/narayana/blob/29270942f17cc553ad1497a41f60fce12e784fb6/ArjunaCore/arjuna/classes/com/arjuna/ats/internal/arjuna/objectstore/LogStore.java#L734