[gnome-shell] shellDBus: Don't assume devices have a node

[Carlos Garnacho <carlosg src gnome org>]

commit e00878ab7510939f56c58a24b85a68776e59a353
Author: Florian Müllner <fmuellner gnome org>
Date:   Fri Sep 20 21:08:45 2019 +0200

    shellDBus: Don't assume devices have a node
    
    Clutter.InputDevice.get_device_node() may return null. Handle that
    case when building the 'AcceleratorActivated' vardict parameter.
    
    https://gitlab.gnome.org/GNOME/gnome-shell/issues/1641

 js/ui/shellDBus.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)
---
diff --git a/js/ui/shellDBus.js b/js/ui/shellDBus.js
index e750c207f9..fca0b64255 100644
--- a/js/ui/shellDBus.js
+++ b/js/ui/shellDBus.js
@@ -151,9 +151,13 @@ var GnomeShell = class {
         let connection = this._dbusImpl.get_connection();
         let info = this._dbusImpl.get_info();
         let params = { 'device-id': GLib.Variant.new('u', device.get_device_id()),
-                       'device-node': GLib.Variant.new('s', device.get_device_node()),
                        'timestamp': GLib.Variant.new('u', timestamp),
                        'action-mode': GLib.Variant.new('u', Main.actionMode) };
+
+        let deviceNode = device.get_device_node();
+        if (deviceNode)
+            params['device-node'] = GLib.Variant.new('s', deviceNode);
+
         connection.emit_signal(destination,
                                this._dbusImpl.get_object_path(),
                                info ? info.name : null,