Roll HarfBuzz to 1.3.0

third_party/harfbuzz-ng/src/hb-ot-layout-gsubgpos-private.hh

 /*
  * Copyright © 2007,2008,2009,2010  Red Hat, Inc.
  * Copyright © 2010,2012  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
@@ skipping 978 matching lines @@
       continue;
 
     unsigned int new_len = buffer->backtrack_len () + buffer->lookahead_len ();
     int delta = new_len - orig_len;
 
     if (!delta)
         continue;
 
     /* Recursed lookup changed buffer len.  Adjust. */
 
-    /* end can't go back past the current match position.
-     * Note: this is only true because we do NOT allow MultipleSubst
-     * with zero sequence len. */
-    end = MAX (MIN((int) match_positions[idx] + 1, (int) new_len), int (end) + delta);
+    end = int (end) + delta;
+    if (end <= match_positions[idx])
+    {
+      /* There can't be any further changes. */
+      assert (end == match_positions[idx]);
+      break;
+    }
 
     unsigned int next = idx + 1; /* next now is the position after the recursed lookup. */
 
     if (delta > 0)
     {
       if (unlikely (delta + count > HB_MAX_CONTEXT_LENGTH))
         break;
     }
     else
     {
@@ skipping 1274 matching lines @@
                 lookupList;     /* LookupList table */
   public:
   DEFINE_SIZE_STATIC (10);
 };
 
 
 } /* namespace OT */
 
 
 #endif /* HB_OT_LAYOUT_GSUBGPOS_PRIVATE_HH */