Comment 4 for bug 1491875

I was totally off on this. It has to do with multiple locks being placed on the tab in this context, not all of which are being removed upon save. I'm not sure that this interface needs to support multiple locks.. so this branch tries to do away with that: collab/phasefx/lp1491875

However, we should test locking and unlocking in all invocations of the MARC editor before accepting this. For reference, bug 1282277 and bug 1282286 touched upon this area via commit e9de9d7e1944ff0b467f204ba898b5f52073cac0