/usr/include/ is in libkf5mime-dev 15.12.3-0ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/KF5/
/usr/include/KF5/kmime_version.h
/usr/include/KF5/KMime/
/usr/include/KF5/KMime/KMime/
/usr/include/KF5/KMime/KMime/Message
/usr/include/KF5/KMime/KMime/DateFormatter
/usr/include/KF5/KMime/KMime/HeaderParsing
/usr/include/KF5/KMime/KMime/MDN
/usr/include/KF5/KMime/KMime/Util
/usr/include/KF5/KMime/KMime/NewsArticle
/usr/include/KF5/KMime/KMime/Types
/usr/include/KF5/KMime/KMime/Codecs
/usr/include/KF5/KMime/KMime/Content
/usr/include/KF5/KMime/KMime/KMimeMessage
/usr/include/KF5/KMime/KMime/ContentIndex
/usr/include/KF5/KMime/KMime/Headers
/usr/include/KF5/KMime/kmime/
/usr/include/KF5/KMime/kmime/kmime_mdn.h
/usr/include/KF5/KMime/kmime/kmime_dateformatter.h
/usr/include/KF5/KMime/kmime/kmime_export.h
/usr/include/KF5/KMime/kmime/kmime_util.h
/usr/include/KF5/KMime/kmime/kmime_headers.h
/usr/include/KF5/KMime/kmime/kmime_content.h
/usr/include/KF5/KMime/kmime/kmime_newsarticle.h
/usr/include/KF5/KMime/kmime/kmime_header_parsing.h
/usr/include/KF5/KMime/kmime/kmime_message.h
/usr/include/KF5/KMime/kmime/kmime_contentindex.h
/usr/include/KF5/KMime/kmime/kmime_types.h