hg: openjfx/11-dev/rt: 8226537: Multi-level Stage::initOwner can crash gnome-shell or X.org server

[johan at lodgon.com]

Changeset: a29ce15af5fd
Author:    tsayao
Date:      2019-06-28 09:42 -0700
URL:       https://hg.openjdk.java.net/openjfx/11-dev/rt/rev/a29ce15af5fd

8226537: Multi-level Stage::initOwner can crash gnome-shell or X.org server
Reviewed-by: kcr, pbansal

! modules/javafx.graphics/src/main/native-glass/gtk/glass_window.cpp