[vte] widget: Redraw when en/disabling SIXEL

[Christian Persch <chpe src gnome org>]

commit 09e71510d1b7061df177d6e3b531aa5cc86b8d65
Author: Christian Persch <chpe src gnome org>
Date:   Sat Aug 8 21:55:09 2020 +0200

    widget: Redraw when en/disabling SIXEL

 src/vteinternal.hh | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/src/vteinternal.hh b/src/vteinternal.hh
index 88c2fe40..8c510912 100644
--- a/src/vteinternal.hh
+++ b/src/vteinternal.hh
@@ -762,6 +762,8 @@ public:
         {
                 auto const changed = m_sixel_enabled != enabled;
                 m_sixel_enabled = m_images_enabled = enabled;
+                if (changed)
+                        invalidate_all();
                 return changed;
         }