What does ‘Rock a hat” mean?

There is the following sentence in Tina Fey’s “Bossypants":

”Don Fay dresses well. He has an artist’s eye for mixing colors and prints. He wears tweedy jackets over sweater vests in the winter and seersucker suits in the summer. His great college ring shows off his well-groomed hands. He can still rock a hat. - P43.”

I don’t understand what “He can still rock a hat” means.” Neither of CED or OED carries “rock a hat” as an idiom. Nor GoogleNgram does.

What does it mean? Is this phrase Tina Fey’s coinage?

I'm pretty sure it means that he looks good in a hat.

Not sure if UrbanDictionary is a good reference, but this is the definition I mean:

Rockin'

Wearing something proudly and/or looking good wearing something.

He's really rockin' that new hat of his!
He's really rockin' that new haircut.

Taken from UrbanDictionary: Rockin'

My eldest son can rock a hat. I am the opposite: even great hats look terrible on me.

To rock a hat is to look great in a hat.

On an errand this weekend, I saw these chic summer hats on display.... They’re designed by Eugenia Kim, a New York based milliner. I was tempted to buy one but I’m not sure I can rock a hat.

and

It's not top brands or being able to rock a hat or a man scarf...
He also can rock a hat like nobody's business...
She’s got the sound and look of a star... The girl can sing, play piano and guitar, and man, can she rock a hat.

I have not been able to find the first use. It doesn't show up once in Ngrams. I'd guess that means it's use is relatively recent. Searching idioms with hat yields no rock a hat for me. There are a lot of colorful idioms involving hats, but I think this one is just jargon at the moment.

To rock a hat is a slang term meaning to wear a hat. How one looks in the hat is not always relevant, although it can refer to looks depending on how the phrase is used.

In this example the only implication is to wear a hat:

I think I will rock a hat for the party tomorrow night.

Whereas in this one it is strongly suggested that Eric looks good in the hat:

Eric can really rock that hat!