IDX_UNKNOWN        91 3rdparty/libwebp/mux/muxedit.c   if (idx == IDX_UNKNOWN && data->size > TAG_SIZE) {
IDX_UNKNOWN        93 3rdparty/libwebp/mux/muxinternal.c   return (idx == IDX_NIL) ? IDX_UNKNOWN : idx;
IDX_UNKNOWN        50 3rdparty/libwebp/mux/muxread.c   SWITCH_ID_LIST(IDX_UNKNOWN, mux->unknown_);
IDX_UNKNOWN       358 3rdparty/libwebp/mux/muxread.c   } else if (idx != IDX_UNKNOWN) {  // A known chunk type.