Deprecate gfe2_reloadable_flag_quic_tls_enforce_valid_sni

PiperOrigin-RevId: 318883809
Change-Id: I9b95e7fdbed1ba22beec30527875630e7cbcfb24

quic/core/tls_server_handshaker.cc

diff --git a/quic/core/tls_server_handshaker.cc b/quic/core/tls_server_handshaker.cc
index 3894556..717d774 100644
--- a/quic/core/tls_server_handshaker.cc
+++ b/quic/core/tls_server_handshaker.cc
@@ -510,14 +510,11 @@
     hostname_ = hostname;
     crypto_negotiated_params_->sni =
         QuicHostnameUtils::NormalizeHostname(hostname_);
-    if (GetQuicReloadableFlag(quic_tls_enforce_valid_sni)) {
-      QUIC_RELOADABLE_FLAG_COUNT(quic_tls_enforce_valid_sni);
-      if (!QuicHostnameUtils::IsValidSNI(hostname_)) {
-        // TODO(b/151676147): Include this error string in the CONNECTION_CLOSE
-        // frame.
-        QUIC_LOG(ERROR) << "Invalid SNI provided: \"" << hostname_ << "\"";
-        return SSL_TLSEXT_ERR_ALERT_FATAL;
-      }
+    if (!QuicHostnameUtils::IsValidSNI(hostname_)) {
+      // TODO(b/151676147): Include this error string in the CONNECTION_CLOSE
+      // frame.
+      QUIC_LOG(ERROR) << "Invalid SNI provided: \"" << hostname_ << "\"";
+      return SSL_TLSEXT_ERR_ALERT_FATAL;
     }
   } else {
     QUIC_LOG(INFO) << "No hostname indicated in SNI";

quic/core/tls_server_handshaker_test.cc

diff --git a/quic/core/tls_server_handshaker_test.cc b/quic/core/tls_server_handshaker_test.cc
index b766dfc..8b60122 100644
--- a/quic/core/tls_server_handshaker_test.cc
+++ b/quic/core/tls_server_handshaker_test.cc
@@ -366,7 +366,6 @@
 }
 
 TEST_F(TlsServerHandshakerTest, RejectInvalidSNI) {
-  SetQuicReloadableFlag(quic_tls_enforce_valid_sni, true);
   server_id_ = QuicServerId("invalid!.example.com", kServerPort, false);
   InitializeFakeClient();
   static_cast<TlsClientHandshaker*>(