Black Ops 3: Leaked MP7?

'Call of Duty: Black Ops 3' is a very easy, enjoyable game. However, the game files contain leaks and possible features that could be added to the game in the foreseeable future. A leak circulating a few months back was a possible 'MP7' addition that was shown in the PC version of the game, as Specialists were spotted with these guns as their Showcase Weapon, then in a class in multiplayer. Is this Treyarch telling us something? Or a well-carried out hack? (Video © Chaos)