[gnome-software/gnome-3-22] snap: Don't attempt to refine snaps without a valid name

[Robert Ancell <rancell src gnome org>]

commit 1cb2e4fc6c1a7dfb9370b247f8c0fa4925df95ff
Author: Robert Ancell <robert ancell canonical com>
Date:   Fri Oct 27 10:10:16 2017 +1300

    snap: Don't attempt to refine snaps without a valid name

 src/plugins/gs-plugin-snap.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/src/plugins/gs-plugin-snap.c b/src/plugins/gs-plugin-snap.c
index ec34bd7..9277443 100644
--- a/src/plugins/gs-plugin-snap.c
+++ b/src/plugins/gs-plugin-snap.c
@@ -371,6 +371,8 @@ gs_plugin_refine_app (GsPlugin *plugin,
        id = gs_app_get_id (app);
        if (id == NULL)
                id = gs_app_get_source_default (app);
+       if (id == NULL)
+               return TRUE;
 
        /* get information from installed snaps */
        local_snap = gs_snapd_list_one (macaroon, discharges, id, cancellable, NULL);