src/java.desktop/share/classes/sun/swing/SwingAccessor.java

@@ -87,10 +87,17 @@
     public interface JLightweightFrameAccessor {
         /**
          * Notifies the JLightweight frame that it needs to update a cursor
          */
         void updateCursor(JLightweightFrame frame);
+
+        /**
+         * Notifies the JLightweight frame embed to JavaFX stage about
+         * its native toplevel window change
+         */
+
+        void overrideNativeWindowHandle(JLightweightFrame frame, long ptr);
     }
 
     /**
      * An accessor for the UIDefaults class.
      */