I see... In Argentina we would say 'Qué cara dura...', and in Spain: 'Que morro...'. Both refer to the face, one is kind of, sucha hard face, and the other is little bit hard to translate, but same concept. Probably it comes to the fact of no showing any shame on the face.
Still, it is friendly as long as you are close to the person, and he or her is a real friend of you. Otherwise it could be offensive or quite unkind, and it's absolutely informal to talk like this.
Hope this helps,