8289606: CustomSecurityManagerTest fails on Mac M1

Reviewed-by: kcr

tests/system/src/test/java/test/robot/helloworld/CustomSecurityManagerTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2022, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -195,7 +195,15 @@ private void doTestFullScreenCommon(SecurityManager sm,
                 assertFalse(propertyState);
             }
             for (int row = 0; row < 2; row++) {
-                int y = row == 0 ? 1 : screenHeight.get() - 2;
+                int h = screenHeight.get();
+                int y;
+                if (row == 0) {
+                    // avoid the top area as it might contain OS-specific UI (Macs with a notch)
+                    y = h / 3;
+                } else {
+                    y = h - 2;
+                }
+
                 for (int col = 0; col < 2; col++) {
                     int x = col == 0 ? 1 : screenWidth.get() - 2;
                     Color color = getColor(x, y);