public Task RemoveLoginAsync(User user, UserLoginInfo login)
{
if (user == null)
{
throw new ArgumentNullException("user");
}
if (login == null)
{
throw new ArgumentNullException("login");
}
externalLoginRepository.DeleteLogin(user.Id, login.LoginProvider, login.ProviderKey);
return(Task.FromResult <object>(null));
}
