/usr/include/libgnomecanvas-2.0/libgnomecanvas/ is in libgnomecanvas2-dev 2.30.3-3.
This file is owned by root:root, with mode 0o755.
..
/usr/include/libgnomecanvas-2.0/libgnomecanvas/gnome-canvas-bpath.h
/usr/include/libgnomecanvas-2.0/libgnomecanvas/gnome-canvas-clipgroup.h
/usr/include/libgnomecanvas-2.0/libgnomecanvas/gnome-canvas-line.h
/usr/include/libgnomecanvas-2.0/libgnomecanvas/gnome-canvas-path-def.h
/usr/include/libgnomecanvas-2.0/libgnomecanvas/gnome-canvas-pixbuf.h
/usr/include/libgnomecanvas-2.0/libgnomecanvas/gnome-canvas-polygon.h
/usr/include/libgnomecanvas-2.0/libgnomecanvas/gnome-canvas-rect-ellipse.h
/usr/include/libgnomecanvas-2.0/libgnomecanvas/gnome-canvas-rich-text.h
/usr/include/libgnomecanvas-2.0/libgnomecanvas/gnome-canvas-shape.h
/usr/include/libgnomecanvas-2.0/libgnomecanvas/gnome-canvas-text.h
/usr/include/libgnomecanvas-2.0/libgnomecanvas/gnome-canvas-util.h
/usr/include/libgnomecanvas-2.0/libgnomecanvas/gnome-canvas-widget.h
/usr/include/libgnomecanvas-2.0/libgnomecanvas/gnome-canvas.h
/usr/include/libgnomecanvas-2.0/libgnomecanvas/libgnomecanvas.h