[autofit] Fix comment.
diff --git a/src/autofit/hbshim.c b/src/autofit/hbshim.c
index cf375a0..cc04815 100644
--- a/src/autofit/hbshim.c
+++ b/src/autofit/hbshim.c
@@ -355,8 +355,9 @@
count++;
#endif
- /* HarfBuzz 0.9.26 and older doesn't validate glyph indices */
- /* returned by `hb_ot_layout_lookup_collect_glyphs'... */
+ /* glyph indices returned by `hb_ot_layout_lookup_collect_glyphs' */
+ /* can be arbitrary: some fonts use fake indices for processing */
+ /* internal to GSUB or GPOS, which is fully valid */
if ( idx >= (hb_codepoint_t)globals->glyph_count )
continue;