[gnome-nibbles/arnaudb/wip/gtk4: 146/188] Adapt to GtkHeaderBar API.

[Arnaud B. <arnaudb src gnome org>]

commit c1a9febd730c3d7011dab5caf73d16b46b935a3d
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Sat May 30 18:08:36 2020 +0200

    Adapt to GtkHeaderBar API.

 src/nibbles-window.vala | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/src/nibbles-window.vala b/src/nibbles-window.vala
index 81ed03a..61f3737 100644
--- a/src/nibbles-window.vala
+++ b/src/nibbles-window.vala
@@ -583,7 +583,7 @@ private class NibblesWindow : ApplicationWindow
         if (game.is_running)
             game.stop ();
 
-        headerbar.set_title (Nibbles.PROGRAM_NAME);
+        set_title (Nibbles.PROGRAM_NAME);
 
         new_game_action.set_enabled (true);
         pause_action.set_enabled (false);
@@ -680,7 +680,7 @@ private class NibblesWindow : ApplicationWindow
         pause_button.show ();
 
         /* Translators: title of the headerbar, while a game is running; the %d is replaced by the level 
number */
-        headerbar.set_title (_("Level %d").printf (game.current_level));        // TODO unduplicate, 1/2
+        set_title (_("Level %d").printf (game.current_level));        // TODO unduplicate, 1/2
         main_stack.set_visible_child_name ("game_box");
 
         main_stack.set_transition_type (StackTransitionType.SLIDE_UP);
@@ -898,7 +898,7 @@ private class NibblesWindow : ApplicationWindow
             button.destroy ();
 
             /* Translators: title of the headerbar, while a game is running; the %d is replaced by the level 
number */
-            headerbar.set_title (_("Level %d").printf (game.current_level));    // TODO unduplicate, 2/2
+            set_title (_("Level %d").printf (game.current_level));    // TODO unduplicate, 2/2
 
             view.show ();