is_focus_sibling

Description:

public bool is_focus_sibling (CellRenderer renderer, CellRenderer sibling)

Returns whether sibling is one of renderer’s focus siblings (see add_focus_sibling).

this	a `GtkCellArea`
renderer	the `GtkCellRenderer` expected to have focus
sibling	the `GtkCellRenderer` to check against `renderer`’s sibling list

true if sibling is a focus sibling of renderer