atdgen makes invalid JSON code if there is an inline record

[irategopher]

I've found an issue when atdgen accepts an inline record definition but generates an invalid code:

File "hello_j.ml", line 221, characters 19-24:
221 |               ob x.field;
                         ^^^^^

hello.atd:
type arithmetic = [ Composite of {field: int} ] <ocaml repr="classic">

Steps to reproduce:

echo 'type arithmetic = [ Composite of {field: int} ] <ocaml repr="classic">' > hello.atd && \
atdgen -t hello.atd && \
atdgen -j hello.atd && \
ocamlfind ocamlc -c hello_t.mli -package atdgen && \
ocamlfind ocamlc -c hello_j.mli -package atdgen && \
ocamlfind ocamlopt -c hello_j.ml -package atdgen