This is a convenience function for CellArea implementations to request size for cell renderers.
It’s important to use this function to request size and then use inner_cell_area at render and event time since this function will add padding around the cell for focus painting.
the CellRenderer to request size for
the Orientation in which to request size
the Widget that this is rendering onto
the allocation contextual size to request for, or -1 if the base request for the orientation is to be returned.
location to store the minimum size, or null
location to store the natural size, or null