During one of the missions in Battlefield Hardline, you can see this guard playing a video game while he's completely oblivious to everything else around him. What game is he playing?
That is Dead Space 2. See this video and it shows that same scene around the 25 second mark. The IGN page for the easter eggs in the game indicate that it is Dead Space 2. I can also tell that is Dead Space 2 because of the blue lines going down the characters back as shown in this picture (which indicates your health in the game):
Other things that give it away is the work bench as shown in the video I linked, and the weapon he is using (it looks like the infamous Plasma Cutter).
Additional information: both of these games are published by Electronic Arts, and share the same developer (Visceral Games).