[vte] draw: Fix unused function warning

[Christian Persch <chpe src gnome org>]

commit b1af917ffbccb516e8cdbb4c624c39615444c423
Author: Christian Persch <chpe src gnome org>
Date:   Thu Nov 21 22:02:51 2019 +0100

    draw: Fix unused function warning

 src/vtedraw.cc | 4 ++++
 1 file changed, 4 insertions(+)
---
diff --git a/src/vtedraw.cc b/src/vtedraw.cc
index 1d13df7c..1ecb5b24 100644
--- a/src/vtedraw.cc
+++ b/src/vtedraw.cc
@@ -1227,6 +1227,8 @@ polygon(cairo_t* cr,
         cairo_fill (cr);
 }
 
+#ifdef WITH_UNICODE_NEXT
+
 static void
 pattern(cairo_t* cr,
         cairo_pattern_t* pattern,
@@ -1242,6 +1244,8 @@ pattern(cairo_t* cr,
         cairo_mask(cr, pattern);
 }
 
+#endif /* WITH_UNICODE_NEXT */
+
 #include "box_drawing.h"
 
 /* Draw the graphic representation of a line-drawing or special graphics