[Integrated] RFR: 8236839: System menubar removed when other menubars are created or modified

[Kevin Rushforth]

Changeset: a74137a1
Author:    Johan Kaving <johan.kaving at looklet.com>
Committer: Kevin Rushforth <kcr at openjdk.org>
Date:      2020-02-07 14:43:29 +0000
URL:       https://git.openjdk.java.net/jfx/commit/a74137a1

8236839: System menubar removed when other menubars are created or modified

Reviewed-by: kcr, aghaisas

! modules/javafx.controls/src/main/java/javafx/scene/control/skin/MenuBarSkin.java
! modules/javafx.controls/src/test/java/test/javafx/scene/control/skin/MenuBarSkinTest.java