Imported Upstream version 3.6.0

Former-commit-id: da6be194a6b1221998fc28233f2503bd61dd9d14

mcs/tests/test-750.cs

@@ -0,0 +1,21 @@
+// Compiler options: -warnaserror -warn:4
+using System;
+
+public interface IA
+{
+	string this[int index] { get; set; }
+}
+
+public interface IB : IA
+{
+	int this[string name] { get; set; }
+	new int this[int index] { get; set; }
+	int this[string namespaceURI, string localName] {get; set;}
+}
+
+class M
+{
+	public static void Main ()
+	{
+	}
+}