score:11
First of all, no backpacks allowed, no bags big enough to bring anything worth the effort.
Secondly, all bags going into any Paris museum are scanned and/or looked through, basically for bombs but a drone might stand out enough for the searcher to take note.
Thirdly, there are guards all through the museum and they will take action, and with Paris on high alerts, I guess police will be involved, even if you just try to outsmart the crowds.
Fourthly, with all art which is potentially in danger from your drone, I think you will see a high bill if they feel they can make it stick.
(Side note)
Most museums state these days that selfie sticks are not allowed. And those are easy to control compared to drones.