Roll HarfBuzz to 1.3.0

third_party/harfbuzz-ng/src/hb-font-private.hh

 /*
  * Copyright © 2009  Red Hat, Inc.
  * Copyright © 2011  Google, Inc.
  *
  *  This is part of HarfBuzz, a text shaping library.
  *
  * Permission is hereby granted, without written agreement and without
  * license or royalty fees, to use, copy, modify, and distribute this
  * software and its documentation for any purpose, provided that the
  * above copyright notice and the following two paragraphs appear in
@@ skipping 487 matching lines @@
       if (0 == strncmp (s, "uni", 3) &&
           hb_codepoint_parse (s + 3, len - 3, 16, &unichar) &&
           get_nominal_glyph (unichar, glyph))
         return true;
     }
 
     return false;
   }
 
   private:
-  inline hb_position_t em_scale (int16_t v, int scale) { return (hb_position_t) (v * (int64_t) scale / face->get_upem ()); }
+  inline hb_position_t em_scale (int16_t v, int scale)
+  {
+    int upem = face->get_upem ();
+    int64_t scaled = v * (int64_t) scale;
+    scaled += scaled >= 0 ? upem/2 : -upem/2; /* Round. */
+    return (hb_position_t) (scaled / upem);
+  }
 };
 
 #define HB_SHAPER_DATA_CREATE_FUNC_EXTRA_ARGS
 #define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_PROTOTYPE(shaper, font);
 #include "hb-shaper-list.hh"
 #undef HB_SHAPER_IMPLEMENT
 #undef HB_SHAPER_DATA_CREATE_FUNC_EXTRA_ARGS
 
 
 #endif /* HB_FONT_PRIVATE_HH */