As part of a former job, I used to do field repair on systems under warranty, so I'll just relay my past experiences:

I've never seen a manufacturer be picky about scratches on a laptop case. They're meant to be lugged around, so nicks and scratches are par for the course and they're designed to take that kind of minor damage. If the case is cracked or the internal posts where screws attach are cracked or broken, then they might assume it was dropped.

But I haven't worked on a Sony laptop under warranty before, so I can't say for certain how they'll treat you. I've had a lot of experience working on IBM & HP laptops, and I'm confident either of them would replace your LCD under warranty with no argument whatsoever.