Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.ServiceModel/System/ServiceModel/Channels/ContextAddressHeader.cs

@@ -0,0 +1,37 @@
+//------------------------------------------------------------
+// Copyright (c) Microsoft Corporation.  All rights reserved.
+//------------------------------------------------------------
+
+namespace System.ServiceModel.Channels
+{
+    using System.Collections.Generic;
+    using System.Runtime;
+    using System.Xml;
+
+    class ContextAddressHeader : AddressHeader
+    {
+        ContextDictionary context;
+
+        public ContextAddressHeader(IDictionary<string, string> context)
+            : base()
+        {
+            Fx.Assert(context != null, "caller must validate");
+            this.context = new ContextDictionary(context);
+        }
+
+        public override string Name
+        {
+            get { return ContextMessageHeader.ContextHeaderName; }
+        }
+
+        public override string Namespace
+        {
+            get { return ContextMessageHeader.ContextHeaderNamespace; }
+        }
+
+        protected override void OnWriteAddressHeaderContents(XmlDictionaryWriter writer)
+        {
+            ContextMessageHeader.WriteHeaderContents(writer, this.context);
+        }
+    }
+}