def self.find_for_facebook_oauth(access_token, signed_in_resource=nil)
  data = access_token['extra']['user_hash']
  if user = User.find_by_email(data["email"])
    user
  else # Create a user with a stub password.
    User.create(:email => data["email"], :password => Devise.friendly_token[0,20])
  end
end