>>6004435[HEAVY SPOILERS]
Godzilla gets 4 forms as it evolves.
That's the second (the first one we actually see in the film when he comes to land).
His eyes are shark-like and still adapted for water at that point, so they're large and don't have a proper 'eyelid'. He instead gets a nictitating membrane that covers his eye from danger like explosives.
In his final form (the one from all the trailers) his membrane looks chrome and reflective, which protects his eyes from the intense light and heat of his own atomic breath.
It's also freaky as shit.