[gnome-nibbles/arnaudb/wip/gtk4: 159/188] Adapt to GtkEventController API, part 2.

[Arnaud B. <arnaudb src gnome org>]

commit 71653ed778f9e65972432e7007a9412893d810ae
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Mon Jun 15 19:24:49 2020 +0200

    Adapt to GtkEventController API, part 2.

 src/preferences-dialog.vala | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/src/preferences-dialog.vala b/src/preferences-dialog.vala
index ae79abb..fa137b4 100644
--- a/src/preferences-dialog.vala
+++ b/src/preferences-dialog.vala
@@ -50,8 +50,9 @@ private class PreferencesDialog : Window
 
     construct
     {
-        key_controller = new EventControllerKey (this);
+        key_controller = new EventControllerKey ();
         key_controller.key_pressed.connect (on_key_pressed);
+        ((Widget) this).add_controller (key_controller);
 
         tree_views = new Gee.ArrayList<TreeView> ();
         tree_views.add (tree_view_1);