[layout] Remove unintentionally added code

src/hb-ot-layout-common.hh

@@ -277,8 +277,6 @@ struct Script
   { return langSys.find_index (tag, index); }
 
   inline bool has_default_lang_sys (void) const { return defaultLangSys != 0; }
-  inline const LangSys& get_default_lang_sys (unsigned int i) const
-  { return get_default_lang_sys (); }
   inline const LangSys& get_default_lang_sys (void) const { return this+defaultLangSys; }
 
   inline bool subset (hb_subset_context_t *c) const