substr            424 base/strings/string_piece.cc StringPiece substr(const StringPiece& self,
substr            430 base/strings/string_piece.cc StringPiece16 substr(const StringPiece16& self,
substr             81 third_party/re2/util/stringpiece.cc StringPiece StringPiece::substr(size_type pos, size_type n) const {