/// <summary>
/// Gets the user id for the specified provider.
/// </summary>
/// <returns>The user id for provider, null if user doesn't have the specified provider present</returns>
public string GetIdForProvider(string provider)
{
Check.Argument.IsStrNotNullOrEmpty(provider, "provider", "Provider can not be null or empty");
return(HasIdentityForProvider(provider) ? nativeBridge.GetUserIdForProvider(provider) : null);
}