message: create srs in verifier_index if it is not passed in
diff: @@ -209,13 +209,13 @@ where
  }
  }
  -impl<G> VerifierIndex<G>
  +impl<G: CommitmentCurve> VerifierIndex<G>
  where
  - G: CommitmentCurve,
  + G::BaseField: PrimeField,
  {
  /// Deserializes a [VerifierIndex] from a file, given a pointer to an SRS and an optional offset in the file.
  pub fn from_file(
  - srs: Arc<SRS<G>>,
  + srs: Option<Arc<SRS<G>>>,
  path: &Path,
  offset: Option<u64>,
  // TODO: we shouldn't have to pass these
  @@ -237,7 +237,15 @@ where
  .map_err(|e| e.to_string())?;
  // fill in the rest
  - verifier_index.srs = srs;
  + verifier_index.srs = match srs {
  + Some(t) => t,
  + None => {
  + let mut srs = SRS::<G>::create(verifier_index.max_poly_size);
  + srs.add_lagrange_basis(verifier_index.domain);
  + Arc::new(srs)
  + }
  + };
  +
  verifier_index.endo = endo;
  verifier_index.fq_sponge_params = fq_sponge_params;
  verifier_index.fr_sponge_params = fr_sponge_params;
  