Appears that only the Toyota OEM glass is treated. Like many others, though, I'm going for the cheaper alternative and having a third-party windshield installed. We have so much road construction where I live, windshields are practially a "consumable" item -- I'd rather not be spending $450 for each replacement.
And anyway, upon reflection, I think the water-shedding is more important for side and rear glass; for the front, there's those convenient windshield wipers that Toyota thoughtfully installed.