Folks, this worked for me too - thanks a lot for the solution!
One thing to note - the Photos app will NOT download the required components if on mobile internet (searching for the issue on the web revealed its an expected behavior for the app, its the way Google coded it). So make sure you are on wifi connection. Once on wifi, the Photos app will download the required components properly (if you enable notifications for photos app, you will see the notification saying its updating the app).