/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/ is in libcegui-mk2-dev 0.8.4+dfsg-4ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/Button.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/Default.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/Editbox.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/FrameWindow.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/ItemEntry.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/ItemListbox.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/ListHeader.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/ListHeaderSegment.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/Listbox.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/MenuItem.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/Menubar.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/Module.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/MultiColumnList.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/MultiLineEditbox.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/PopupMenu.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/ProgressBar.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/ScrollablePane.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/Scrollbar.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/Slider.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/Static.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/StaticImage.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/StaticText.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/TabButton.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/TabControl.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/Titlebar.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/ToggleButton.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/Tooltip.h
/usr/include/cegui-0.8.4/CEGUI/WindowRendererSets/Core/Tree.h