Facebook has the buying power to put together a solid hardware production team. I don't think Google has much internal hardware production knowledge right now, aside from the knowledge they bought when they acquired Motorola. Before that, they mostly made things through hardware partners like HTC, Samsung, and LG. I think they produce the Chromecast internally, but it's not much fancier than a USB stick. I'm sure they are quickly learning, but Facebook is also already buying up hardware companies and they have been building their own custom servers for internal use for years.