Fix Orphan<AnyStruct>.
Fix Orphan<AnyStruct>.

mologie/capnproto,hntrmrrs/capnproto,maurer/capnproto,pjulien/capnproto,joliss/capnproto,maurer/capnproto,vladon/capnproto,pjulien/capnproto,mologie/capnproto,mrdomino/capnproto,rcrowder/capnproto,mrdomino/capnproto,rcrowder/capnproto,pjulien/capnproto,hntrmrrs/capnproto,vladon/capnproto,joliss/capnproto,maurer/capnproto,mrdomino/capnproto,mologie/capnproto,jparyani/capnproto,joliss/capnproto,rcrowder/capnproto,vladon/capnproto,hntrmrrs/capnproto,jparyani/capnproto,jparyani/capnproto