There is a function in the EditRole.aspx.cs

private void Page_Load(object sender, System.EventArgs e)
        {
            // Put user code to initialize the page here
            PhilePrincipal currentPrincipal = (PhilePrincipal)Context.User;
            if (!currentPrincipal.HasPermission((int)AccountsPerm issions.UpdateRoles))
            {
                Response.Write("You don't have sufficient permission to be using this page.");
                Response.End();
            }

            if (!Page.IsPostBack)
            {
                DoInitialDataBind();
            }
        }

I can't understand what is about with the "(PhilePrincipal)Context.User"

Who can tell me?

That casts the default context.user into the principal object created with the file