LockFD is the generic implementation that can be embedded in FileDescriptionImpl implementations. Unique lock ID is maintained in vfs.FileDescription and is created on demand. Updates #1480 PiperOrigin-RevId: 315604825
Updates #1197, #1198, #1672 PiperOrigin-RevId: 310432006
Updates #1035 PiperOrigin-RevId: 306968644