title: Can app.UseErrorHandler() access error details?
body: <p>In my MVC4 app I had a global.asax.cs override of <code>Application_Error(object sender, EventArgs e)</code> where I could extract the <code>exception</code>, <code>statusCode</code> and <code>requestedUrl</code> (for handling 404). That would get sent to my controller and the error page would be different for 404s vs 5xx (these get a stack trace). I don't see how to get this same info to my Error action using <code>UseErrorHandler()</code>. Am I using the right approach in ASP.NET Core?</p>