There's also a permissions warning that states that these apps "will be able to run when you are using applications in virtual reality mode." It's not clear exactly what form virtual reality mode will take, but the name suggests it will be more comprehensive than the Cardboard app Google offers currently.
Android N is just the beginning
Google's clearly making a big push into VR, so this doesn't come as a huge surprise. The company recently dedicated a whole section of its store to VR and it's said to be working on new VR headsets, including one which doesn't require tethering to a smartphone or other device.
That's interesting because such a headset would need a built in interface to run VR apps from, so the virtual reality mode mentioned in Android N could be that interface.
In related news, Ars Technica also spotted a mention of "sustained performance mode" in the Android N framework. Mobile chips are good for quick bursts of power, but tend to struggle when pushed for an extended period.
A sustained performance mode sounds like it could aim to change that, which would help handsets cope with VR applications, which are typically CPU-intensive, for an extended period. This is all guess work for now, but there's mounting evidence that Google's VR ambitions go way, way beyond a cardboard headset.
Damn, you scary VR