small fixup to hb-cairo-utils

util/hb-cairo-utils.h

@@ -24,10 +24,11 @@
  * Google Author(s): Matthias Clasen
  */
 
-#ifndef HB_CAIRO_UTILS_H
+#pragma once
-#define HB_CAIRO_UTILS_H
 
-extern "C" {
+#include <hb.h>
+
+HB_BEGIN_DECLS
 
 static inline cairo_operator_t
 hb_paint_composite_mode_to_cairo (hb_paint_composite_mode_t mode)
@@ -99,6 +100,4 @@ void hb_cairo_paint_sweep_gradient (cairo_t *cr,
                                     float x0, float y0,
                                     float start_angle, float end_angle);
 
-}
+HB_END_DECLS
-
-#endif