[arrays] Add hb_ubytes_t for unsigned char
diff --git a/src/hb-array.hh b/src/hb-array.hh
index 33837b0..d4df165 100644
--- a/src/hb-array.hh
+++ b/src/hb-array.hh
@@ -268,6 +268,7 @@
 
 
 typedef hb_array_t<const char> hb_bytes_t;
+typedef hb_array_t<const unsigned char> hb_ubytes_t;
 
 
 #endif /* HB_ARRAY_HH */