Make sure the hi-res icons are available for StartupDialog

Author: jisedlac

visualvm/startup/src/org/graalvm/visualvm/modules/startup/dialogs/StartupDialog.java

@@ -75,6 +75,9 @@ public static JDialog create(String caption, String message, int messageType) {
         icons.add(ImageUtilities.loadImage("org/netbeans/core/startup/frame24.gif", true)); // NOI18N
         icons.add(ImageUtilities.loadImage("org/netbeans/core/startup/frame32.gif", true)); // NOI18N
         icons.add(ImageUtilities.loadImage("org/netbeans/core/startup/frame48.gif", true)); // NOI18N
+        icons.add(ImageUtilities.loadImage("org/netbeans/core/startup/frame256.png", true)); // NOI18N
+        icons.add(ImageUtilities.loadImage("org/netbeans/core/startup/frame512.png", true)); // NOI18N
+        icons.add(ImageUtilities.loadImage("org/netbeans/core/startup/frame1024.png", true)); // NOI18N
         d.setIconImages(icons);
 
         d.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);