[evince] flatpak: disable evince's thumbnailer

[Germán Poo-Caamaño <gpoo src gnome org>]

commit 75a421b8bdea689607b114b5ffaf6f561de47939
Author: Jason Crain <jcrain src gnome org>
Date:   Tue Jul 16 00:03:07 2019 -0600

    flatpak: disable evince's thumbnailer
    
    It's not useful in the flatpak.

 build-aux/flatpak/org.gnome.Evince.json | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/build-aux/flatpak/org.gnome.Evince.json b/build-aux/flatpak/org.gnome.Evince.json
index 3a2e6dc9..64ea9462 100644
--- a/build-aux/flatpak/org.gnome.Evince.json
+++ b/build-aux/flatpak/org.gnome.Evince.json
@@ -145,7 +145,8 @@
             "config-opts" : [
                 "-Dnautilus=false",
                 "-Dgtk_doc=false",
-                "-Dintrospection=false"
+                "-Dintrospection=false",
+                               "-Dthumbnailer=false"
             ],
             "sources" : [
                 {