Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/XamlBuildTask/Microsoft/Build/Tasks/Xaml/DelegatingTaskItem.cs

@@ -0,0 +1,72 @@
+// <copyright>
+//   Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+
+namespace Microsoft.Build.Tasks.Xaml
+{
+    using System;
+    using System.Collections;
+    using Microsoft.Build.Framework;
+
+    // In Dev10, we allowed use of non-remotable ITaskItems. While there's not really any good scenario
+    // for those, we need to support that for back-compat. So we wrap each provided TaskItems in an MBRO.
+    internal class DelegatingTaskItem : MarshalByRefObject, ITaskItem
+    {
+        private ITaskItem underlyingItem;
+
+        // This is different from TaskItem.ctor(ITaskItem): it's a wrapper, not a clone.
+        // So any changes are propagated back to the original object.
+        public DelegatingTaskItem(ITaskItem underlyingItem)
+        {
+            this.underlyingItem = underlyingItem;
+        }
+
+        public string ItemSpec
+        {
+            get
+            {
+                return this.underlyingItem.ItemSpec;
+            }
+
+            set
+            {
+                this.underlyingItem.ItemSpec = value;
+            }
+        }
+
+        public int MetadataCount
+        {
+            get { return this.underlyingItem.MetadataCount; }
+        }
+
+        public ICollection MetadataNames
+        {
+            get { return this.underlyingItem.MetadataNames; }
+        }
+
+        public IDictionary CloneCustomMetadata()
+        {
+            return this.underlyingItem.CloneCustomMetadata();
+        }
+
+        public void CopyMetadataTo(ITaskItem destinationItem)
+        {
+            this.underlyingItem.CopyMetadataTo(destinationItem);
+        }
+
+        public string GetMetadata(string metadataName)
+        {
+            return this.underlyingItem.GetMetadata(metadataName);
+        }
+
+        public void RemoveMetadata(string metadataName)
+        {
+            this.underlyingItem.RemoveMetadata(metadataName);
+        }
+
+        public void SetMetadata(string metadataName, string metadataValue)
+        {
+            this.underlyingItem.SetMetadata(metadataName, metadataValue);
+        }
+    }
+}