/usr/include/cegui-0.8.7/CEGUI/widgets/ is in libcegui-mk2-dev 0.8.7-1.3+b2.
This file is owned by root:root, with mode 0o755.
..
/usr/include/cegui-0.8.7/CEGUI/widgets/All.h
/usr/include/cegui-0.8.7/CEGUI/widgets/ButtonBase.h
/usr/include/cegui-0.8.7/CEGUI/widgets/ClippedContainer.h
/usr/include/cegui-0.8.7/CEGUI/widgets/ComboDropList.h
/usr/include/cegui-0.8.7/CEGUI/widgets/Combobox.h
/usr/include/cegui-0.8.7/CEGUI/widgets/DefaultWindow.h
/usr/include/cegui-0.8.7/CEGUI/widgets/DragContainer.h
/usr/include/cegui-0.8.7/CEGUI/widgets/Editbox.h
/usr/include/cegui-0.8.7/CEGUI/widgets/FrameWindow.h
/usr/include/cegui-0.8.7/CEGUI/widgets/GridLayoutContainer.h
/usr/include/cegui-0.8.7/CEGUI/widgets/GroupBox.h
/usr/include/cegui-0.8.7/CEGUI/widgets/HorizontalLayoutContainer.h
/usr/include/cegui-0.8.7/CEGUI/widgets/ItemEntry.h
/usr/include/cegui-0.8.7/CEGUI/widgets/ItemListBase.h
/usr/include/cegui-0.8.7/CEGUI/widgets/ItemListbox.h
/usr/include/cegui-0.8.7/CEGUI/widgets/LayoutCell.h
/usr/include/cegui-0.8.7/CEGUI/widgets/LayoutContainer.h
/usr/include/cegui-0.8.7/CEGUI/widgets/ListHeader.h
/usr/include/cegui-0.8.7/CEGUI/widgets/ListHeaderSegment.h
/usr/include/cegui-0.8.7/CEGUI/widgets/Listbox.h
/usr/include/cegui-0.8.7/CEGUI/widgets/ListboxItem.h
/usr/include/cegui-0.8.7/CEGUI/widgets/ListboxTextItem.h
/usr/include/cegui-0.8.7/CEGUI/widgets/MenuBase.h
/usr/include/cegui-0.8.7/CEGUI/widgets/MenuItem.h
/usr/include/cegui-0.8.7/CEGUI/widgets/Menubar.h
/usr/include/cegui-0.8.7/CEGUI/widgets/MultiColumnList.h
/usr/include/cegui-0.8.7/CEGUI/widgets/MultiLineEditbox.h
/usr/include/cegui-0.8.7/CEGUI/widgets/PopupMenu.h
/usr/include/cegui-0.8.7/CEGUI/widgets/ProgressBar.h
/usr/include/cegui-0.8.7/CEGUI/widgets/PushButton.h
/usr/include/cegui-0.8.7/CEGUI/widgets/RadioButton.h
/usr/include/cegui-0.8.7/CEGUI/widgets/ScrollablePane.h
/usr/include/cegui-0.8.7/CEGUI/widgets/Scrollbar.h
/usr/include/cegui-0.8.7/CEGUI/widgets/ScrolledContainer.h
/usr/include/cegui-0.8.7/CEGUI/widgets/ScrolledItemListBase.h
/usr/include/cegui-0.8.7/CEGUI/widgets/SequentialLayoutContainer.h
/usr/include/cegui-0.8.7/CEGUI/widgets/Slider.h
/usr/include/cegui-0.8.7/CEGUI/widgets/Spinner.h
/usr/include/cegui-0.8.7/CEGUI/widgets/TabButton.h
/usr/include/cegui-0.8.7/CEGUI/widgets/TabControl.h
/usr/include/cegui-0.8.7/CEGUI/widgets/Thumb.h
/usr/include/cegui-0.8.7/CEGUI/widgets/Titlebar.h
/usr/include/cegui-0.8.7/CEGUI/widgets/ToggleButton.h
/usr/include/cegui-0.8.7/CEGUI/widgets/Tooltip.h
/usr/include/cegui-0.8.7/CEGUI/widgets/Tree.h
/usr/include/cegui-0.8.7/CEGUI/widgets/TreeItem.h
/usr/include/cegui-0.8.7/CEGUI/widgets/VerticalLayoutContainer.h