[gvfs/gnome-3-20] daemon: Handle NULL certificates properly

[Ondrej Holy <oholy src gnome org>]

commit 4dca9bcd306e16b60b6577734951027cf85081e7
Author: Ondrej Holy <oholy redhat com>
Date:   Tue Jun 28 16:07:03 2016 +0200

    daemon: Handle NULL certificates properly
    
    Webdav backend crashes if libsoup returns NULL certificate. Ftp backend
    may be also affected. The crash may happen if you try to connect with
    "davs://" ("ftps://") to a server, which is not TLS-enabled. The backend
    fails properly with libsoup error thanks to this patch.
    
    https://bugzilla.redhat.com/show_bug.cgi?id=1350820

 daemon/gvfsdaemonutils.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/daemon/gvfsdaemonutils.c b/daemon/gvfsdaemonutils.c
index 49999a8..77c7b1b 100644
--- a/daemon/gvfsdaemonutils.c
+++ b/daemon/gvfsdaemonutils.c
@@ -333,6 +333,9 @@ gvfs_accept_certificate (GMountSource *mount_source,
   gboolean handled, aborted = FALSE;
   char *certificate_str, *reason, *message;
 
+  if (certificate == NULL)
+    return FALSE;
+
   certificate_str = certificate_to_string (certificate);
   reason = certificate_flags_to_string (errors);
   message = g_strdup_printf (_("The site's identity can't be verified:"