/usr/include/KF5/KAlarmCal/kalarmcal/ is in libkf5alarmcalendar-dev 4:15.12.3-0ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/KF5/KAlarmCal/kalarmcal/alarmtext.h
/usr/include/KF5/KAlarmCal/kalarmcal/collectionattribute.h
/usr/include/KF5/KAlarmCal/kalarmcal/compatibilityattribute.h
/usr/include/KF5/KAlarmCal/kalarmcal/datetime.h
/usr/include/KF5/KAlarmCal/kalarmcal/eventattribute.h
/usr/include/KF5/KAlarmCal/kalarmcal/identities.h
/usr/include/KF5/KAlarmCal/kalarmcal/kacalendar.h
/usr/include/KF5/KAlarmCal/kalarmcal/kaevent.h
/usr/include/KF5/KAlarmCal/kalarmcal/kalarmcal_export.h
/usr/include/KF5/KAlarmCal/kalarmcal/karecurrence.h
/usr/include/KF5/KAlarmCal/kalarmcal/repetition.h
/usr/include/KF5/KAlarmCal/kalarmcal/version.h