[coretext] Add hb_coretext_face_get_cg_font()

Not sure if it's useful, but it was missing.

src/hb-coretext.cc

@@ -91,6 +91,14 @@ _hb_coretext_shaper_face_data_destroy (hb_coretext_shaper_face_data_t *data)
   free (data);
 }
 
+CGFontRef
+hb_coretext_face_get_ct_font (hb_face_t *face)
+{
+  if (unlikely (!hb_coretext_shaper_face_data_ensure (face))) return NULL;
+  hb_coretext_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
+  return face_data->cg_font;
+}
+
 
 /*
  * shaper font data
@@ -149,19 +157,19 @@ _hb_coretext_shaper_shape_plan_data_destroy (hb_coretext_shaper_shape_plan_data_
 {
 }
 
-
-/*
- * shaper
- */
-
 CTFontRef
 hb_coretext_font_get_ct_font (hb_font_t *font)
 {
-  if (unlikely (!hb_coretext_shaper_font_data_ensure (font))) return 0;
+  if (unlikely (!hb_coretext_shaper_font_data_ensure (font))) return NULL;
   hb_coretext_shaper_font_data_t *font_data = HB_SHAPER_DATA_GET (font);
   return font_data->ct_font;
 }
 
+
+/*
+ * shaper
+ */
+
 hb_bool_t
 _hb_coretext_shape (hb_shape_plan_t    *shape_plan,
 		    hb_font_t          *font,

src/hb-coretext.h

@@ -34,6 +34,9 @@
 HB_BEGIN_DECLS
 
 
+CGFontRef
+hb_coretext_face_get_cg_font (hb_face_t *face);
+
 CTFontRef
 hb_coretext_font_get_ct_font (hb_font_t *font);