Imported Upstream version 3.6.0

Former-commit-id: da6be194a6b1221998fc28233f2503bd61dd9d14

external/aspnetwebstack/src/System.Web.Mvc/HttpNotFoundResult.cs

@@ -0,0 +1,20 @@
+// Copyright (c) Microsoft Corporation. All rights reserved. See License.txt in the project root for license information.
+
+using System.Net;
+
+namespace System.Web.Mvc
+{
+    public class HttpNotFoundResult : HttpStatusCodeResult
+    {
+        public HttpNotFoundResult()
+            : this(null)
+        {
+        }
+
+        // NotFound is equivalent to HTTP status 404.
+        public HttpNotFoundResult(string statusDescription)
+            : base(HttpStatusCode.NotFound, statusDescription)
+        {
+        }
+    }
+}