fn fresh_impl_header_normalized<'tcx>(
infcx: &InferCtxt<'tcx>,
param_env: ParamEnv<'tcx>,
impl_def_id: DefId
) -> ImplHeader<'tcx>
fn fresh_impl_header_normalized<'tcx>(
infcx: &InferCtxt<'tcx>,
param_env: ParamEnv<'tcx>,
impl_def_id: DefId
) -> ImplHeader<'tcx>