/usr/include/Qt5GStreamer/QGlib/ is in libqt5gstreamer-dev 1.2.0-3.
This file is owned by root:root, with mode 0o755.
..
/usr/include/Qt5GStreamer/QGlib/Connect
/usr/include/Qt5GStreamer/QGlib/Error
/usr/include/Qt5GStreamer/QGlib/Global
/usr/include/Qt5GStreamer/QGlib/Init
/usr/include/Qt5GStreamer/QGlib/Object
/usr/include/Qt5GStreamer/QGlib/ParamSpec
/usr/include/Qt5GStreamer/QGlib/Quark
/usr/include/Qt5GStreamer/QGlib/RefPointer
/usr/include/Qt5GStreamer/QGlib/Signal
/usr/include/Qt5GStreamer/QGlib/Type
/usr/include/Qt5GStreamer/QGlib/Value
/usr/include/Qt5GStreamer/QGlib/connect.h
/usr/include/Qt5GStreamer/QGlib/connectimpl.h
/usr/include/Qt5GStreamer/QGlib/emitimpl.h
/usr/include/Qt5GStreamer/QGlib/error.h
/usr/include/Qt5GStreamer/QGlib/global.h
/usr/include/Qt5GStreamer/QGlib/init.h
/usr/include/Qt5GStreamer/QGlib/object.h
/usr/include/Qt5GStreamer/QGlib/paramspec.h
/usr/include/Qt5GStreamer/QGlib/qglib_signal.h
/usr/include/Qt5GStreamer/QGlib/quark.h
/usr/include/Qt5GStreamer/QGlib/refpointer.h
/usr/include/Qt5GStreamer/QGlib/type.h
/usr/include/Qt5GStreamer/QGlib/value.h
/usr/include/Qt5GStreamer/QGlib/wrap.h