Imported Upstream version 4.0.0~alpha1

Former-commit-id: 806294f5ded97629b74c85c09952f2a74fe182d9

external/referencesource/System.IdentityModel/System/IdentityModel/Tokens/ComputedKeyAlgorithms.cs

@@ -0,0 +1,22 @@
+//-----------------------------------------------------------------------
+// <copyright file="ComputedKeyAlgorithms.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//-----------------------------------------------------------------------
+
+
+using System;
+
+namespace System.IdentityModel.Tokens
+{
+    /// <summary>
+    /// Used in the RST to indicated the desired algorithm used to compute key based on 
+    /// the combined entropies from both token requestor and token issuer.
+    /// </summary>
+    public static class ComputedKeyAlgorithms
+    {
+#pragma warning disable 1591
+        public const string Psha1 = "http://schemas.microsoft.com/idfx/computedkeyalgorithm/psha1";
+#pragma warning restore 1591
+    }
+}