prevent infinite loop if gtk_menu_popup() fails, fixes #15387

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@74624 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/window.cpp

@@ -4368,6 +4368,13 @@ bool wxWindowGTK::DoPopupMenu( wxMenu *menu, int x, int y )
                   gtk_get_current_event_time()
                 );
 
+    // it is possible for gtk_menu_popup() to fail
+    if (!gtk_widget_get_visible(GTK_WIDGET(menu->m_menu)))
+    {
+        menu->m_popupShown = false;
+        return false;
+    }
+
     while (menu->m_popupShown)
     {
         gtk_main_iteration();