This one doesn't declare winners, so it's probably not the exact same addon, but I use
XLoot and
XLootMaster. XLoot provides a replacement loot frame, with a link in the corner to link all the loot to the chat frame of your choice. XLootMaster is an extension to XLoot, and provides very easy access to link loot one at a time with a preset message calling for rolls, and will track legitimate rolls for you too. Like I said earlier though, it doesn't announce the winners for me. (Or is that just because I've never turned that option on before? I don't know) Good luck