message: Use the correct enum in switch statments.
  ecdsa_key_format.params().curve() is the proto enum, so we should also use the proto enum in the switch statement.
diff: @@ -79,13 +79,13 @@ StatusOr<EcdsaPrivateKey> EcdsaSignKeyManager::DeriveKey(
  // will result in the same keys being generated.
  int random_bytes_used = 0;
  switch (ecdsa_key_format.params().curve()) {
  - case subtle::EllipticCurveType::NIST_P256:
  + case google::crypto::tink::EllipticCurveType::NIST_P256:
  random_bytes_used = 16;
  break;
  - case subtle::EllipticCurveType::NIST_P384:
  + case google::crypto::tink::EllipticCurveType::NIST_P384:
  random_bytes_used = 24;
  break;
  - case subtle::EllipticCurveType::NIST_P521:
  + case google::crypto::tink::EllipticCurveType::NIST_P521:
  random_bytes_used = 32;
  break;
  default:
  