[goobox] do not use a popover for the app menu

[Paolo Bacchilega <paobac src gnome org>]

commit ca2d5401186fc69d3d8ac255278119b08a3286a1
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Sat Dec 29 12:55:22 2018 +0100

    do not use a popover for the app menu
    
    the window could be too short to show the entire popover

 src/goo-window.c | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/src/goo-window.c b/src/goo-window.c
index 8152922..7ddc88f 100644
--- a/src/goo-window.c
+++ b/src/goo-window.c
@@ -2330,6 +2330,7 @@ goo_window_construct (GooWindow    *window,
                _gtk_menu_button_set_style_for_header_bar (button);
                gtk_menu_button_set_direction (GTK_MENU_BUTTON (button), GTK_ARROW_NONE);
                gtk_menu_button_set_menu_model (GTK_MENU_BUTTON (button), menu);
+               gtk_menu_button_set_use_popover (GTK_MENU_BUTTON (button), FALSE);
                gtk_widget_show_all (button);
                gtk_header_bar_pack_end (GTK_HEADER_BAR (headerbar), button);