Just the stock launcher.Both of my Nexus devices did this once after the 4.4.2 update. I simply reset the wallpaper. I can't remember if my N7 was running the launcher from the Nexus 5. (I know my N5 was as I just switched to action launcher earlier this week.) What launcher are you using?
Sent from my Nexus 7 (2013) using AC Forums mobile app.