relnote: Deprecate --reloadable_flag_quic_use_hash_in_scup

net/quic/crypto/quic_crypto_server_config.cc

Index: net/quic/crypto/quic_crypto_server_config.cc
diff --git a/net/quic/crypto/quic_crypto_server_config.cc b/net/quic/crypto/quic_crypto_server_config.cc
index 11b96ffdaf696e009da13e8f30b8964b50e61bbd..f3ef158e275f09cd3154b080f277ffd8d1ba9155 100644
--- a/net/quic/crypto/quic_crypto_server_config.cc
+++ b/net/quic/crypto/quic_crypto_server_config.cc
@@ -1200,20 +1200,11 @@ bool QuicCryptoServerConfig::BuildServerConfigUpdateMessage(
   scoped_refptr<ProofSource::Chain> chain;
   string signature;
   string cert_sct;
-  if (FLAGS_quic_use_hash_in_scup) {
-    if (!proof_source_->GetProof(server_ip, params.sni, serialized, version,
-                                 chlo_hash, params.x509_ecdsa_supported, &chain,
-                                 &signature, &cert_sct)) {
-      DVLOG(1) << "Server: failed to get proof.";
-      return false;
-    }
-  } else {
-    if (!proof_source_->GetProof(
-            server_ip, params.sni, serialized, version, params.client_nonce,
-            params.x509_ecdsa_supported, &chain, &signature, &cert_sct)) {
-      DVLOG(1) << "Server: failed to get proof.";
-      return false;
-    }
+  if (!proof_source_->GetProof(server_ip, params.sni, serialized, version,
+                               chlo_hash, params.x509_ecdsa_supported, &chain,
+                               &signature, &cert_sct)) {
+    DVLOG(1) << "Server: failed to get proof.";
+    return false;
   }
 
   const string compressed = CompressChain(
@@ -1267,15 +1258,9 @@ void QuicCryptoServerConfig::BuildServerConfigUpdateMessage(
           this, version, compressed_certs_cache, common_cert_sets, params,
           std::move(message), std::move(cb)));
 
-  if (FLAGS_quic_use_hash_in_scup) {
-    proof_source_->GetProof(server_ip, params.sni, serialized, version,
-                            chlo_hash, params.x509_ecdsa_supported,
-                            std::move(proof_source_cb));
-  } else {
-    proof_source_->GetProof(server_ip, params.sni, serialized, version,
-                            params.client_nonce, params.x509_ecdsa_supported,
-                            std::move(proof_source_cb));
-  }
+  proof_source_->GetProof(server_ip, params.sni, serialized, version, chlo_hash,
+                          params.x509_ecdsa_supported,
+                          std::move(proof_source_cb));
 }
 
 QuicCryptoServerConfig::BuildServerConfigUpdateMessageProofSourceCallback::