/usr/include/libinfinity-0.6/libinfinity/server/ is in libinfinity-0.6-dev 0.6.7-1build1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/libinfinity-0.6/libinfinity/server/infd-account-storage.h
/usr/include/libinfinity-0.6/libinfinity/server/infd-chat-filesystem-format.h
/usr/include/libinfinity-0.6/libinfinity/server/infd-directory.h
/usr/include/libinfinity-0.6/libinfinity/server/infd-filesystem-account-storage.h
/usr/include/libinfinity-0.6/libinfinity/server/infd-filesystem-storage.h
/usr/include/libinfinity-0.6/libinfinity/server/infd-note-plugin.h
/usr/include/libinfinity-0.6/libinfinity/server/infd-progress-request.h
/usr/include/libinfinity-0.6/libinfinity/server/infd-request.h
/usr/include/libinfinity-0.6/libinfinity/server/infd-server-pool.h
/usr/include/libinfinity-0.6/libinfinity/server/infd-session-proxy.h
/usr/include/libinfinity-0.6/libinfinity/server/infd-storage.h
/usr/include/libinfinity-0.6/libinfinity/server/infd-tcp-server.h
/usr/include/libinfinity-0.6/libinfinity/server/infd-xml-server.h
/usr/include/libinfinity-0.6/libinfinity/server/infd-xmpp-server.h