[gtk/switch-glyph] switch: Avoid problems with glyph availability

[Matthias Clasen <matthiasc src gnome org>]

commit 6a4ce55a69c5ecbbf06bc905ac0bfdd04f64bb66
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Jan 23 12:02:27 2019 -0500

    switch: Avoid problems with glyph availability
    
    If none of the glyphs we want are available, fall
    back to using empty strings here, rather than causing
    critical warnings.

 gtk/gtkswitch.c | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/gtk/gtkswitch.c b/gtk/gtkswitch.c
index 1d42f572a9..4c49e243ed 100644
--- a/gtk/gtkswitch.c
+++ b/gtk/gtkswitch.c
@@ -302,12 +302,14 @@ gtk_switch_create_pango_layouts (GtkSwitch *self)
   const char *on_glyphs[] = {
     "⏽", /* U+23FD POWER ON SYMBOL */
     "❙", /* U+2759 MEDIUM VERTICAL BAR */
+    ""
   };
 
   /* Glyphs for the OFF state, in descending order of preference */
   const char *off_glyphs[] = {
     "⭘", /* U+2B58 HEAVY CIRCLE */
     "○", /* U+25CB WHITE CIRCLE */
+    ""
   };
   int i;