Function compute_bidirectional_outlives_clauses 

fn compute_bidirectional_outlives_clauses<'tcx>(
    tcx: TyCtxt<'tcx>,
    opaque_own_params: &[GenericParamDef],
    clauses: &mut Vec<(Clause<'tcx>, Span)>,
)

Opaques have duplicated lifetimes and we need to compute bidirectional outlives clauses to enforce that these lifetimes stay in sync.