Cleanup/fix content variants mapping

src/Umbraco.Web/Models/Mapping/MappingOperationOptionsExtensions.cs

@@ -0,0 +1,45 @@
+using AutoMapper;
+
+namespace Umbraco.Web.Models.Mapping
+{
+    /// <summary>
+    /// Provides extension methods for AutoMapper's <see cref="IMappingOperationOptions"/>.
+    /// </summary>
+    internal static class MappingOperationOptionsExtensions
+    {
+        private const string CultureKey = "MappingOperationOptions.Culture";
+        private const string IncludedPropertiesKey = "MappingOperationOptions.IncludeProperties";
+
+        /// <summary>
+        /// Gets the context culture.
+        /// </summary>
+        public static string GetCulture(this IMappingOperationOptions options)
+        {
+            return options.Items.TryGetValue(CultureKey, out var obj) && obj is string s ? s : null;
+        }
+
+        /// <summary>
+        /// Sets a context culture.
+        /// </summary>
+        public static void SetCulture(this IMappingOperationOptions options, string culture)
+        {
+            options.Items[CultureKey] = culture;
+        }
+
+        /// <summary>
+        /// Get included properties.
+        /// </summary>
+        public static string[] GetIncludedProperties(this IMappingOperationOptions options)
+        {
+            return options.Items.TryGetValue(IncludedPropertiesKey, out var obj) && obj is string[] s ? s : null;
+        }
+
+        /// <summary>
+        /// Sets included properties.
+        /// </summary>
+        public static void SetIncludedProperties(this IMappingOperationOptions options, string[] properties)
+        {
+            options.Items[IncludedPropertiesKey] = properties;
+        }
+    }
+}