Update harfbuzz-ng to 0.9.24

third_party/harfbuzz-ng/src/hb-ot-shape-normalize.cc

 /*
  * Copyright © 2011,2012  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
  * all copies of this software.
@@ skipping 114 matching lines @@
 skip_char (hb_buffer_t *buffer)
 {
   buffer->skip_glyph ();
 }
 
 /* Returns 0 if didn't decompose, number of resulting characters otherwise. */
 static inline unsigned int
 decompose (const hb_ot_shape_normalize_context_t *c, bool shortest, hb_codepoint_t ab)
 {
   hb_codepoint_t a, b, a_glyph, b_glyph;
+  hb_buffer_t * const buffer = c->buffer;
+  hb_font_t * const font = c->font;
 
   if (!c->decompose (c, ab, &a, &b) ||
-      (b && !c->font->get_glyph (b, 0, &b_glyph)))
+      (b && !font->get_glyph (b, 0, &b_glyph)))
     return 0;
 
-  bool has_a = c->font->get_glyph (a, 0, &a_glyph);
+  bool has_a = font->get_glyph (a, 0, &a_glyph);
   if (shortest && has_a) {
     /* Output a and b */
-    output_char (c->buffer, a, a_glyph);
+    output_char (buffer, a, a_glyph);
     if (likely (b)) {
-      output_char (c->buffer, b, b_glyph);
+      output_char (buffer, b, b_glyph);
       return 2;
     }
     return 1;
   }
 
   unsigned int ret;
   if ((ret = decompose (c, shortest, a))) {
     if (b) {
-      output_char (c->buffer, b, b_glyph);
+      output_char (buffer, b, b_glyph);
       return ret + 1;
     }
     return ret;
   }
 
   if (has_a) {
-    output_char (c->buffer, a, a_glyph);
+    output_char (buffer, a, a_glyph);
     if (likely (b)) {
-      output_char (c->buffer, b, b_glyph);
+      output_char (buffer, b, b_glyph);
       return 2;
     }
     return 1;
   }
 
   return 0;
 }
 
 /* Returns 0 if didn't decompose, number of resulting characters otherwise. */
 static inline unsigned int
@@ skipping 33 matching lines @@
   else if (decompose_compatibility (c, buffer->cur().codepoint))
     skip_char (buffer);
   else
     next_char (buffer, glyph); /* glyph is initialized in earlier branches. */
 }
 
 static inline void
 handle_variation_selector_cluster (const hb_ot_shape_normalize_context_t *c, unsigned int end)
 {
   hb_buffer_t * const buffer = c->buffer;
+  hb_font_t * const font = c->font;
   for (; buffer->idx < end - 1;) {
     if (unlikely (buffer->unicode->is_variation_selector (buffer->cur(+1).codepoint))) {
       /* The next two lines are some ugly lines... But work. */
-      c->font->get_glyph (buffer->cur().codepoint, buffer->cur(+1).codepoint, &buffer->cur().glyph_index());
-      buffer->replace_glyphs (2, 1, &buffer->cur().codepoint);
+      if (font->get_glyph (buffer->cur().codepoint, buffer->cur(+1).codepoint, &buffer->cur().glyph_index()))
+      {
+        buffer->replace_glyphs (2, 1, &buffer->cur().codepoint);
+      }
+      else
+      {
+        /* Just pass on the two characters separately, let GSUB do its magic. */
+        set_glyph (buffer->cur(), font);
+        buffer->next_glyph ();
+        set_glyph (buffer->cur(), font);
+        buffer->next_glyph ();
+      }
+      /* Skip any further variation selectors. */
+      while (buffer->idx < end && unlikely (buffer->unicode->is_variation_selector (buffer->cur().codepoint)))
+      {
+        set_glyph (buffer->cur(), font);
+        buffer->next_glyph ();
+      }
     } else {
-      set_glyph (buffer->cur(), c->font);
+      set_glyph (buffer->cur(), font);
       buffer->next_glyph ();
     }
   }
   if (likely (buffer->idx < end)) {
-    set_glyph (buffer->cur(), c->font);
+    set_glyph (buffer->cur(), font);
     buffer->next_glyph ();
   }
 }
 
 static inline void
 decompose_multi_char_cluster (const hb_ot_shape_normalize_context_t *c, unsigned int end)
 {
   hb_buffer_t * const buffer = c->buffer;
   /* TODO Currently if there's a variation-selector we give-up, it's just too hard. */
   for (unsigned int i = buffer->idx; i < end; i++)
@@ skipping 144 matching lines @@
 
     /* Blocked, or doesn't compose. */
     buffer->next_glyph ();
 
     if (_hb_glyph_info_get_modified_combining_class (&buffer->prev()) == 0)
       starter = buffer->out_len - 1;
   }
   buffer->swap_buffers ();
 
 }