Imported Upstream version 4.0.0~alpha1

Former-commit-id: 806294f5ded97629b74c85c09952f2a74fe182d9

external/referencesource/mscorlib/system/diagnostics/ICustomDebuggerNotification.cs

@@ -0,0 +1,25 @@
+// ==++==
+// 
+//   Copyright (c) Microsoft Corporation.  All rights reserved.
+// 
+// ==--==
+/*============================================================
+**
+** Class:  ICustomDebuggerNotification
+**
+** This interface is implemented by classes that support custom debugger notifications.
+**
+===========================================================*/
+namespace System.Diagnostics {
+    
+    using System;
+    // Defines an interface indicating that a custom debugger notification is requested under specific 
+    // conditions. Users should implement this interface to be used as an argument to 
+    // System.Diagnostics.Debugger.CustomNotification.  
+    // 
+    // @dbgtodo [....]: when this goes public, it must be replaced by a custom attribute
+    internal interface ICustomDebuggerNotification
+    {
+        // Interface does not need to be marked with the serializable attribute
+    }
+}