Only allow one-on-one calls from friends

One-on-one voice calls should be limited to friends only. The call button is way too easy to misclick on both mobile and on desktop, thereby accidentally dialing the person. It also does not make sense to call someone on voice who is not your friend. Skype and Snapchat have controls that allow you to limit calling to friends only. If you tried, it would tell you that you needed to add the person as a friend first before making the call.