Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Xml/System/Xml/XmlXapResolver.cs

@@ -0,0 +1,30 @@
+using System;
+using System.IO;
+using System.ComponentModel;
+
+namespace System.Xml
+{
+    [Obsolete("This API supports the .NET Framework infrastructure and is not intended to be used directly from your code.", true)]
+    [EditorBrowsable(EditorBrowsableState.Never)]
+    public class XmlXapResolver : XmlResolver
+    {
+        [Obsolete("This API supports the .NET Framework infrastructure and is not intended to be used directly from your code.", true)]
+        [EditorBrowsable(EditorBrowsableState.Never)]
+        public XmlXapResolver() { }
+
+        //can't mark obsolete because we get warning as error in the 
+        //build system. however, since the object cannot be constructed, 
+        //the third party dev cannot somehow write this line of code
+        [EditorBrowsable(EditorBrowsableState.Never)]
+        public override object GetEntity(Uri absoluteUri, string role, Type ofObjectToReturn)
+        {
+            //we throw what the user could naturally expect if networking capabilities weren't available
+            //which is a reasonable thing in designer mode
+            throw new XmlException(Res.Xml_XapResolverCannotOpenUri, absoluteUri.ToString(), default(Exception), null);
+        }
+
+        [Obsolete("This API supports the .NET Framework infrastructure and is not intended to be used directly from your code.", true)]
+        [EditorBrowsable(EditorBrowsableState.Never)]
+        public static void RegisterApplicationResourceStreamResolver(IApplicationResourceStreamResolver appStreamResolver) { }
+    }
+}