Update harfbuzz-ng to 0.9.24

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

Index: third_party/harfbuzz-ng/src/hb-buffer-private.hh
diff --git a/third_party/harfbuzz-ng/src/hb-buffer-private.hh b/third_party/harfbuzz-ng/src/hb-buffer-private.hh
index a8cf770244612196ae5270d4735e4a1846d41b2c..d3ed4491ed9ba587cd348cf3d924e1d4a2c94c15 100644
--- a/third_party/harfbuzz-ng/src/hb-buffer-private.hh
+++ b/third_party/harfbuzz-ng/src/hb-buffer-private.hh
@@ -103,6 +103,8 @@ struct hb_buffer_t {
 
   inline unsigned int backtrack_len (void) const
   { return have_output? out_len : idx; }
+  inline unsigned int lookahead_len (void) const
+  { return len - idx; }
   inline unsigned int next_serial (void) { return serial++; }
 
   HB_INTERNAL void allocate_var (unsigned int byte_i, unsigned int count, const char *owner);
@@ -134,6 +136,7 @@ struct hb_buffer_t {
   HB_INTERNAL void output_info (const hb_glyph_info_t &glyph_info);
   /* Copies glyph at idx to output but doesn't advance idx */
   HB_INTERNAL void copy_glyph (void);
+  HB_INTERNAL bool move_to (unsigned int i); /* i is output-buffer index. */
   /* Copies glyph at idx to output and advance idx.
    * If there's no output, just advance idx. */
   inline void
@@ -181,8 +184,10 @@ struct hb_buffer_t {
   { return likely (size < allocated) ? true : enlarge (size); }
 
   HB_INTERNAL bool make_room_for (unsigned int num_in, unsigned int num_out);
+  HB_INTERNAL bool shift_forward (unsigned int count);
 
-  HB_INTERNAL void *get_scratch_buffer (unsigned int *size);
+  typedef long scratch_buffer_t;
+  HB_INTERNAL scratch_buffer_t *get_scratch_buffer (unsigned int *size);
 
   inline void clear_context (unsigned int side) { context_len[side] = 0; }
 };