Returns whether sibling is one of renderer's focus siblings (see gtk_cell_area_add_focus_sibling()).
the GtkCellRenderer expected to have focus
the GtkCellRenderer to check against renderer's sibling list
TRUE if sibling is a focus sibling of renderer Since 3.0
See Implementation
Returns whether sibling is one of renderer's focus siblings (see gtk_cell_area_add_focus_sibling()).