[retro-gtk] flatpak: Allow access to the dconf config dir

[Adrien Plazas <aplazas src gnome org>]

commit 71ced18f0b056c4553bab1ddb583470cad201ef0
Author: Adrien Plazas <kekun plazas laposte net>
Date:   Wed Jun 20 13:18:03 2018 +0200

    flatpak: Allow access to the dconf config dir
    
    This is needed to check if the GTK+ Inspector is enabled and hence to
    allow its usage.

 flatpak/org.gnome.Retro.DemoSamplesTest.json | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/flatpak/org.gnome.Retro.DemoSamplesTest.json b/flatpak/org.gnome.Retro.DemoSamplesTest.json
index 829d3c6..48d3b70 100644
--- a/flatpak/org.gnome.Retro.DemoSamplesTest.json
+++ b/flatpak/org.gnome.Retro.DemoSamplesTest.json
@@ -7,6 +7,8 @@
     "tags": ["nightly"],
     "desktop-file-name-prefix": "(Nightly) ",
     "finish-args": [
+        /* GTK+ Inspector access */
+        "--env=DCONF_USER_CONFIG_DIR=.config/dconf",
         /* X11 + XShm access */
         "--share=ipc", "--socket=x11",
         /* Wayland access */