/usr/include/hippo-canvas-1/ is in libhippocanvas-dev 0.3.1-1.1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/hippo-canvas-1/hippo/
/usr/include/hippo-canvas-1/hippo/hippo-animation-manager.h
/usr/include/hippo-canvas-1/hippo/hippo-animation.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-box.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-container.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-context.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-gradient.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-image-button.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-image.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-item.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-layout.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-link.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-style.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-text.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-theme-engine.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-theme-image.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-theme.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-util.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-widget.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-widgets.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas-window.h
/usr/include/hippo-canvas-1/hippo/hippo-canvas.h
/usr/include/hippo-canvas-1/hippo/hippo-event.h
/usr/include/hippo-canvas-1/hippo/hippo-graphics.h