[API] font: move user_data before destroy()

This is the common convention for language binding tools.

src/hb-ft.c

diff --git a/src/hb-ft.c b/src/hb-ft.c
index e696fe8..96c035a 100644
--- a/src/hb-ft.c
+++ b/src/hb-ft.c
@@ -189,7 +189,7 @@
 
   return hb_blob_create ((const char *) buffer, length,
 			 HB_MEMORY_MODE_WRITABLE,
-			 free, buffer);
+			 buffer, free);
 }
 
 
@@ -206,11 +206,11 @@
 			   (unsigned int) ft_face->stream->size,
 			   /* TODO: Check FT_FACE_FLAG_EXTERNAL_STREAM? */
 			   HB_MEMORY_MODE_READONLY_MAY_MAKE_WRITABLE,
-			   destroy, ft_face);
+			   ft_face, destroy);
     face = hb_face_create_for_data (blob, ft_face->face_index);
     hb_blob_destroy (blob);
   } else {
-    face = hb_face_create_for_tables (get_table, destroy, ft_face);
+    face = hb_face_create_for_tables (get_table, ft_face, destroy);
   }
 
   return face;
@@ -247,7 +247,7 @@
   font = hb_font_create ();
   hb_font_set_funcs (font,
 		     hb_ft_get_font_funcs (),
-		     destroy, ft_face);
+		     ft_face, destroy);
   hb_font_set_scale (font,
 		     ((uint64_t) ft_face->size->metrics.x_scale * (uint64_t) ft_face->units_per_EM) >> 16,
 		     ((uint64_t) ft_face->size->metrics.y_scale * (uint64_t) ft_face->units_per_EM) >> 16);