/usr/share/gocode/src/golang.org/x/text/internal/number/ is in golang-golang-x-text-dev 0.0~git20170627.0.6353ef0-1ubuntu2.
This file is owned by root:root, with mode 0o755.
..
/usr/share/gocode/src/golang.org/x/text/internal/number/common.go
/usr/share/gocode/src/golang.org/x/text/internal/number/decimal.go
/usr/share/gocode/src/golang.org/x/text/internal/number/decimal_test.go
/usr/share/gocode/src/golang.org/x/text/internal/number/format.go
/usr/share/gocode/src/golang.org/x/text/internal/number/format_test.go
/usr/share/gocode/src/golang.org/x/text/internal/number/gen.go
/usr/share/gocode/src/golang.org/x/text/internal/number/gen_common.go
/usr/share/gocode/src/golang.org/x/text/internal/number/number.go
/usr/share/gocode/src/golang.org/x/text/internal/number/number_test.go
/usr/share/gocode/src/golang.org/x/text/internal/number/pattern.go
/usr/share/gocode/src/golang.org/x/text/internal/number/pattern_test.go
/usr/share/gocode/src/golang.org/x/text/internal/number/roundingmode_string.go
/usr/share/gocode/src/golang.org/x/text/internal/number/tables.go
/usr/share/gocode/src/golang.org/x/text/internal/number/tables_test.go