Don't think that is a film. Pretty sure it's an anti-chip / anti-rock coating. You can buy them for aftermarket/as a body shop. 3M & duplicolor make one... Probably other brands out there.
In an OEM application, I'm not sure if it is on top of the normal clear, or in lieu of normal clear coat? I've seen it on numerous cars from the factory. I know my 13' VW CC had some along the rockers. Should definitely be on both sides though!