Merge pull request #925 from umbraco/temp-U4-7394

Fixes: U4-7394 Missing maxFilseSize variable from web.config in the b…

src/Umbraco.Web/Editors/BackOfficeController.cs

@@ -1,11 +1,13 @@
 using System;
 using System.Collections.Generic;
+using System.Configuration;
 using System.Globalization;
 using System.IO;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
 using System.Web;
+using System.Web.Configuration;
 using System.Web.Mvc;
 using System.Web.UI;
 using ClientDependency.Core.Config;
@@ -177,6 +179,13 @@ namespace Umbraco.Web.Editors
             return new JsonNetResult { Data = gridConfig.EditorsConfig.Editors, Formatting = Formatting.Indented };
         }
 
+        private string GetMaxRequestLength()
+        {
+            var section = ConfigurationManager.GetSection("system.web/httpRuntime") as HttpRuntimeSection;
+            if (section == null) return string.Empty;
+            return section.MaxRequestLength.ToString();
+        }
+
         /// <summary>
         /// Returns the JavaScript object representing the static server variables javascript object
         /// </summary>
@@ -340,6 +349,10 @@ namespace Umbraco.Web.Editors
                                 "imageFileTypes",
                                 string.Join(",", UmbracoConfig.For.UmbracoSettings().Content.ImageFileTypes)
                             },
+                            {
+                                "maxFileSize",
+                                GetMaxRequestLength()
+                            },
                             {"keepUserLoggedIn", UmbracoConfig.For.UmbracoSettings().Security.KeepUserLoggedIn},
                             {"cssPath", IOHelper.ResolveUrl(SystemDirectories.Css).TrimEnd('/')},
                         }