[gnome-calculator/wip/cdavis/gtk4] Fixed basic mode not loading initially

[Robert Roth <robertroth src gnome org>]

commit 5149199b70a230eeb5a12f565e16572d78705521
Author: Robert Roth <robert roth off gmail com>
Date:   Wed Oct 13 14:15:32 2021 +0300

    Fixed basic mode not loading initially

 src/math-buttons.vala | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/math-buttons.vala b/src/math-buttons.vala
index 2d748c87..77d72ebd 100644
--- a/src/math-buttons.vala
+++ b/src/math-buttons.vala
@@ -27,7 +27,7 @@ public class MathButtons : Gtk.Box
         get { return _mode; }
         set
         {
-            if (_mode == value)
+            if (_mode == value && converter != null )
                 return;
             _mode = value;