/usr/include/mirserver/mir/frontend/ is in libmirserver-dev 0.1.8+14.04.20140411-0ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/mirserver/mir/frontend/connected_sessions.h
/usr/include/mirserver/mir/frontend/connector.h
/usr/include/mirserver/mir/frontend/connector_report.h
/usr/include/mirserver/mir/frontend/display_changer.h
/usr/include/mirserver/mir/frontend/event_sink.h
/usr/include/mirserver/mir/frontend/fd_sets.h
/usr/include/mirserver/mir/frontend/message_processor.h
/usr/include/mirserver/mir/frontend/message_processor_report.h
/usr/include/mirserver/mir/frontend/protobuf_message_sender.h
/usr/include/mirserver/mir/frontend/protobuf_session_creator.h
/usr/include/mirserver/mir/frontend/screencast.h
/usr/include/mirserver/mir/frontend/session.h
/usr/include/mirserver/mir/frontend/session_authorizer.h
/usr/include/mirserver/mir/frontend/session_creator.h
/usr/include/mirserver/mir/frontend/session_mediator_report.h
/usr/include/mirserver/mir/frontend/shell.h
/usr/include/mirserver/mir/frontend/surface.h
/usr/include/mirserver/mir/frontend/surface_id.h
/usr/include/mirserver/mir/frontend/template_protobuf_message_processor.h