Probly Donaire by UD. Pac was really raw at this stage as visible in the Sasakul fight. He managed to defend it once and lost to Singsurat thereafter. Donaire however has the skillset to dominate.
This would be a young faster morales vs pac. Nonito by KO after good fight in the early rounds. Ud for Nonito would be likely as well. Counter puncher are Pacs kryptonite
I would think Donaire would win easily. If we are talking about the Donaire that KO Mthalane then Donaire by KO before the 10. A face first brawler would be tailor made for the short hooks. Vic has one of the toughest chins around, while Pacquiao had a questionable chin (but perhaps some of it had more to do with walking in/being off balance) so it's going to be a bad night.
Donaire Donaire imo is a better fighter than PAC more complete better defense jab and counter puncher. Donaire is the truth.