EDIT: Seems it's just a visual bug. I just tested it and it did no change. Caught an Applin to test with 41HP. It healed 2 HP which is the normal amount.
Yeah the Ability pops up. I can't really tell how much it heals since I wasn't the user of it.The message triggers, but the ability doesn't.
That being said, I'm interested on this visual bug. Does the Ripen message pop up with all items that can be "used" (triggering the use animation) by a Pokémon (e.g. Focus Sash, Normal Gem)? Or is it just the berries and "usable" recovery items (Leftovers)?
If it's the latter, then Ripen should have an effect on Leftovers, but for some reason it doesn't.