Slight refactor and cleanup

src/Umbraco.Web/Trees/ContentTreeController.cs

@@ -207,6 +207,9 @@ namespace Umbraco.Web.Trees
             return HasPathAccess(entity, queryStrings);
         }
 
+        internal override IEnumerable<IUmbracoEntity> GetChildrenFromEntityService(int entityId)
+            => Services.EntityService.GetChildren(entityId, UmbracoObjectType).ToList();
+
         /// <summary>
         /// Returns a collection of all menu items that can be on a content node
         /// </summary>