U4-9935 UmbracoHelper doesn't have querying methods for handling UDI

src/Umbraco.Web/PublishedContentQueryExtensions.cs

@@ -0,0 +1,23 @@
+using System;
+using Umbraco.Core;
+using Umbraco.Core.Models;
+
+namespace Umbraco.Web
+{
+    public static class PublishedContentQueryExtensions
+    {
+        /// <summary>
+        /// Gets a content item from the cache
+        /// </summary>
+        /// <param name="contentQuery"></param>
+        /// <param name="id"></param>
+        /// <returns></returns>
+        public static IPublishedContent TypedContent(this ITypedPublishedContentQuery contentQuery, Udi id)
+        {
+            var guidUdi = id as GuidUdi;
+            if (guidUdi == null)
+                throw new InvalidOperationException("UDIs for content items must be " + typeof(GuidUdi));
+            return contentQuery.TypedContent(guidUdi.Guid);
+        }
+    }
+}