Imported Upstream version 3.6.0

Former-commit-id: da6be194a6b1221998fc28233f2503bd61dd9d14

mcs/class/System.Web.Mvc3/Mvc/ControllerDescriptorCache.cs

@@ -0,0 +1,14 @@
+namespace System.Web.Mvc {
+    using System;
+
+    internal sealed class ControllerDescriptorCache : ReaderWriterCache<Type, ControllerDescriptor> {
+
+        public ControllerDescriptorCache() {
+        }
+
+        public ControllerDescriptor GetDescriptor(Type controllerType, Func<ControllerDescriptor> creator) {
+            return FetchOrCreateItem(controllerType, creator);
+        }
+
+    }
+}