Wrapped owin middleware config

This wraps owin middle ware configuration within a work context scope.

Fixes #6991

src/Orchard/Environment/DefaultOrchardShell.cs

@@ -55,6 +55,7 @@ namespace Orchard.Environment {
             var appBuilder = new AppBuilder();
             appBuilder.Properties["host.AppName"] = _shellSettings.Name;
 
+            using (var scope = _workContextAccessor.CreateWorkContextScope()) {
                 var orderedMiddlewares = _owinMiddlewareProviders
                     .SelectMany(p => p.GetOwinMiddlewares())
                     .OrderBy(obj => obj.Priority, new FlatPositionComparer());
@@ -62,6 +63,7 @@ namespace Orchard.Environment {
                 foreach (var middleware in orderedMiddlewares) {
                     middleware.Configure(appBuilder);
                 }
+            }
 
             // Register the Orchard middleware after all others.
             appBuilder.UseOrchard();