JBR-7764: Disable window decorations in test/jb/java/awt/Window/RestoreFromFullScreen.java, so that the test doesn't fail spuriously on some WMs

Author: tsarn

test/jdk/jb/java/awt/Window/RestoreFromFullScreen.java

@@ -62,6 +62,7 @@ public static void main(String[] args) throws Exception {
     private static void initUI() {
         frame = new JFrame("RestoreFromFullScreen");
         frame.setBounds(200, 200, INITIAL_WIDTH, INITIAL_HEIGHT);
+        frame.setUndecorated(true);
         frame.setVisible(true);
     }