[recipes] Warn if we don't have the desktop portals

[Matthias Clasen <matthiasc src gnome org>]

commit c94ca4db4ea7bb5a3d7202bd8a86c213fd8ebeb5
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Jan 18 07:19:44 2017 -0500

    Warn if we don't have the desktop portals
    
    This is not great, but better than silently doing nothing
    and leaving people to wonder.

 src/gr-image-viewer.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/gr-image-viewer.c b/src/gr-image-viewer.c
index d5c5c70..5b9adbd 100644
--- a/src/gr-image-viewer.c
+++ b/src/gr-image-viewer.c
@@ -501,7 +501,7 @@ open_filechooser (GrImageViewer *viewer)
                                                  GTK_DIALOG_MODAL|GTK_DIALOG_DESTROY_WITH_PARENT,
                                                  GTK_MESSAGE_ERROR,
                                                  GTK_BUTTONS_OK,
-                                                 _("The system is missing the desktop portals needed to open 
files from inside a flatpak sandbox."));
+                                                 _("Missing the desktop portals needed to open files from 
inside a flatpak sandbox. Please install xdg-desktop-portal and xdg-desktop-portal-gtk on your system."));
                 g_signal_connect (dialog, "response", G_CALLBACK (gtk_widget_destroy), NULL);
                 gtk_widget_show (dialog);
                 return;