[network-manager-applet] applet: fix crash in activate_vpn_cb()

[Beniamino Galvani <bgalvani src gnome org>]

commit 083c5b5d7498d0f75a1a0948522e4cfa5667fd7c
Author: Beniamino Galvani <bgalvani redhat com>
Date:   Mon Apr 10 10:53:25 2017 +0200

    applet: fix crash in activate_vpn_cb()
    
    The return value of g_dbus_error_get_remote_error() can be NULL.
    
    https://bugzilla.redhat.com/show_bug.cgi?id=1440277

 src/applet.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/applet.c b/src/applet.c
index 921dcf2..812877d 100644
--- a/src/applet.c
+++ b/src/applet.c
@@ -1022,7 +1022,7 @@ activate_vpn_cb (GObject *client,
                title = _("VPN Connection Failed");
 
                name = g_dbus_error_get_remote_error (error);
-               if (strstr (name, "ServiceStartFailed")) {
+               if (name && strstr (name, "ServiceStartFailed")) {
                        msg = g_strdup_printf (_("\nThe VPN connection “%s” failed because the VPN service 
failed to start.\n\n%s"),
                                               info->vpn_name, error->message);
                } else {