Function rustfmt_nightly::items::rewrite_where_clause_rfc_style

fn rewrite_where_clause_rfc_style(
    context: &RewriteContext<'_>, 
    where_clause: &WhereClause, 
    shape: Shape, 
    terminator: &str, 
    span_end: Option<BytePos>, 
    span_end_before_where: BytePos, 
    where_clause_option: WhereClauseOption
) -> Option<String>