/usr/include/KF5/KGAPI/kgapi/contacts/ is in libkf5gapi-dev 5.1.0-1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/KF5/KGAPI/kgapi/contacts/contact.h
/usr/include/KF5/KGAPI/kgapi/contacts/contactcreatejob.h
/usr/include/KF5/KGAPI/kgapi/contacts/contactdeletejob.h
/usr/include/KF5/KGAPI/kgapi/contacts/contactfetchjob.h
/usr/include/KF5/KGAPI/kgapi/contacts/contactfetchphotojob.h
/usr/include/KF5/KGAPI/kgapi/contacts/contactmodifyjob.h
/usr/include/KF5/KGAPI/kgapi/contacts/contactsgroup.h
/usr/include/KF5/KGAPI/kgapi/contacts/contactsgroupcreatejob.h
/usr/include/KF5/KGAPI/kgapi/contacts/contactsgroupdeletejob.h
/usr/include/KF5/KGAPI/kgapi/contacts/contactsgroupfetchjob.h
/usr/include/KF5/KGAPI/kgapi/contacts/contactsgroupmodifyjob.h
/usr/include/KF5/KGAPI/kgapi/contacts/kgapicontacts_export.h