That scene also have us a little of Chopper's backstory: she found him on Ryloth during the Clone Wars. Was he the property of a Jedi? The Republic forces or a separatist droid? In a way I think the latter may the the most interesting possibility.
Speaking of Chopper, having recently re-watched "Always Two There Are", I wonder if that mini probe droid installed some sort of malware into him, when it temporarily deactivated him. It would possibly explain Kanan's "everywhere we go, we run into those guys" line in the recent season 2 trailer - The Inquisitors could be tracking the rebels via Chopper.