[gnome-software] snap: Fix screenshots being duplicated

[Robert Ancell <rancell src gnome org>]

commit 242b5f777d0aad4c6ddf2e0123ba8a3448fbcf1b
Author: Robert Ancell <robert ancell canonical com>
Date:   Wed Jun 14 16:40:01 2017 +1200

    snap: Fix screenshots being duplicated

 plugins/snap/gs-plugin-snap.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/plugins/snap/gs-plugin-snap.c b/plugins/snap/gs-plugin-snap.c
index ae00ccb..2103df7 100644
--- a/plugins/snap/gs-plugin-snap.c
+++ b/plugins/snap/gs-plugin-snap.c
@@ -493,7 +493,7 @@ gs_plugin_refine_app (GsPlugin *plugin,
                gs_app_set_developer_name (app, snapd_snap_get_developer (store_snap));
 
                screenshots = snapd_snap_get_screenshots (store_snap);
-               if (screenshots != NULL && screenshots->len > 0) {
+               if (screenshots != NULL && gs_app_get_screenshots (app)->len == 0) {
                        guint i;
 
                        for (i = 0; i < screenshots->len; i++) {