You can formulate a million and one situations like this, some of which could never happen, some of which could and a few that have. I don't really see the point of your question, many aircraft types have suffered uncommanded movement of various flight controls and surfaces, it is not a problem peculiar to Airbus.
If fly the A320/321 so if it happened to me (assuming one of us noticed in time) above V1 then I guess I would select the flap handle to 0 then back to the t/o setting. If that didn't work then I would just do my best to salvage the situation as best I could with power and pitch. If the a/c weight, runway length and obstructions etc. etc. are on my side then we would get away with it and if not then we are going to have a big accident and that would that I suppose. Excrement happens!.