Cleanup: Delete QuicCryptoStream::TlsVersion().

Envoy now uses hardcoded TLS version strings directly, removing the need for this method in the QUIC crypto core. This function is not used anywhere in production, doesn't need flag protection.

PiperOrigin-RevId: 949748511

quiche/quic/core/quic_crypto_stream.cc

diff --git a/quiche/quic/core/quic_crypto_stream.cc b/quiche/quic/core/quic_crypto_stream.cc
index aaf399f..16a9484 100644
--- a/quiche/quic/core/quic_crypto_stream.cc
+++ b/quiche/quic/core/quic_crypto_stream.cc
@@ -690,10 +690,5 @@
   return group;
 }
 
-// IETF QUIC only uses TLS 1.3.
-absl::string_view QuicCryptoStream::TlsVersion() const {
-  return "TLS_VERSION_1_3";
-}
-
 #undef ENDPOINT  // undef for jumbo builds
 }  // namespace quic

quiche/quic/core/quic_crypto_stream.h

diff --git a/quiche/quic/core/quic_crypto_stream.h b/quiche/quic/core/quic_crypto_stream.h
index 0576e3d..84e0c02 100644
--- a/quiche/quic/core/quic_crypto_stream.h
+++ b/quiche/quic/core/quic_crypto_stream.h
@@ -193,8 +193,6 @@
   absl::string_view CiphersuiteString() const;
   // Returns the TLS group string in use.
   absl::string_view TlsGroupString() const;
-  // Returns the TLS version in use.
-  absl::string_view TlsVersion() const;
 
   // Called to cancel retransmission of unencrypted crypto stream data.
   void NeuterUnencryptedStreamData();

quiche/quic/core/tls_client_handshaker_test.cc

diff --git a/quiche/quic/core/tls_client_handshaker_test.cc b/quiche/quic/core/tls_client_handshaker_test.cc
index 826d402..251183b 100644
--- a/quiche/quic/core/tls_client_handshaker_test.cc
+++ b/quiche/quic/core/tls_client_handshaker_test.cc
@@ -325,7 +325,6 @@
   EXPECT_NE(stream()->Ciphersuite(), nullptr);
   EXPECT_NE(stream()->TlsGroupId(), 0);
   EXPECT_FALSE(stream()->TlsGroupString().empty());
-  EXPECT_EQ(stream()->TlsVersion(), "TLS_VERSION_1_3");
 }
 
 #if BORINGSSL_API_VERSION >= 41

quiche/quic/core/tls_server_handshaker_test.cc

diff --git a/quiche/quic/core/tls_server_handshaker_test.cc b/quiche/quic/core/tls_server_handshaker_test.cc
index 3f48cf2..66616ad 100644
--- a/quiche/quic/core/tls_server_handshaker_test.cc
+++ b/quiche/quic/core/tls_server_handshaker_test.cc
@@ -72,7 +72,6 @@
 
 const char kServerHostname[] = "test.example.com";
 const uint16_t kServerPort = 443;
-constexpr absl::string_view kTlsVersion = "TLS_VERSION_1_3";
 
 struct TestParams {
   ParsedQuicVersion version;
@@ -1797,7 +1796,6 @@
   EXPECT_NE(cipher_string, "");
   EXPECT_NE(tls_group_id, 0);
   EXPECT_NE(tls_group_string, "");
-  EXPECT_EQ(server_stream()->TlsVersion(), kTlsVersion);
 
   // Call ResetSsl. This should cache the SSL info.
   TlsServerHandshaker* handshaker =
@@ -1813,7 +1811,6 @@
   EXPECT_EQ(server_stream()->CiphersuiteString(), cipher_string);
   EXPECT_EQ(server_stream()->TlsGroupId(), tls_group_id);
   EXPECT_EQ(server_stream()->TlsGroupString(), tls_group_string);
-  EXPECT_EQ(server_stream()->TlsVersion(), kTlsVersion);
 }
 
 }  // namespace