[font] Fix internal sign of x/y_scale

Should have been done as part of da975419884a535281745f30f4b32fee0bc8a7a1

diff --git a/src/hb-font-private.hh b/src/hb-font-private.hh
index cd74e08..3c6cc1c 100644 (file)
--- a/src/hb-font-private.hh
+++ b/src/hb-font-private.hh
@@ -84,8 +84,8 @@ struct _hb_font_t {
 
   hb_face_t *face;
 
-  unsigned int x_scale;
-  unsigned int y_scale;
+  int x_scale;
+  int y_scale;
 
   unsigned int x_ppem;
   unsigned int y_ppem;