Deprecate gfe2_reloadable_flag_quic_tls_use_token_in_session_cache.

PiperOrigin-RevId: 438557393
diff --git a/quic/core/crypto/quic_client_session_cache.cc b/quic/core/crypto/quic_client_session_cache.cc
index 5ce935d..24b5588 100644
--- a/quic/core/crypto/quic_client_session_cache.cc
+++ b/quic/core/crypto/quic_client_session_cache.cc
@@ -87,8 +87,7 @@
     state->application_state =
         std::make_unique<ApplicationState>(*iter->second->application_state);
   }
-  if (GetQuicReloadableFlag(quic_tls_use_token_in_session_cache) &&
-      !iter->second->token.empty()) {
+  if (!iter->second->token.empty()) {
     state->token = iter->second->token;
     // Clear token after use.
     iter->second->token.clear();
diff --git a/quic/core/http/end_to_end_test.cc b/quic/core/http/end_to_end_test.cc
index ac10d0f..95b274a 100644
--- a/quic/core/http/end_to_end_test.cc
+++ b/quic/core/http/end_to_end_test.cc
@@ -1718,27 +1718,14 @@
   server_thread_->Pause();
   server_session = GetServerSession();
   server_connection = GetServerConnection();
-  if (!GetQuicReloadableFlag(quic_tls_use_token_in_session_cache)) {
-    // Address token is reused.
-    if (server_session != nullptr && server_connection != nullptr) {
-      // Verify address is validated via validating token received in INITIAL
-      // packet.
-      EXPECT_FALSE(server_connection->GetStats()
-                       .address_validated_via_decrypting_packet);
-      EXPECT_TRUE(server_connection->GetStats().address_validated_via_token);
-    } else {
-      ADD_FAILURE() << "Missing server connection";
-    }
+  // Verify address token is only used once.
+  if (server_session != nullptr && server_connection != nullptr) {
+    // Verify address is validated via decrypting packet.
+    EXPECT_TRUE(
+        server_connection->GetStats().address_validated_via_decrypting_packet);
+    EXPECT_FALSE(server_connection->GetStats().address_validated_via_token);
   } else {
-    // Verify address token is only used once.
-    if (server_session != nullptr && server_connection != nullptr) {
-      // Verify address is validated via decrypting packet.
-      EXPECT_TRUE(server_connection->GetStats()
-                      .address_validated_via_decrypting_packet);
-      EXPECT_FALSE(server_connection->GetStats().address_validated_via_token);
-    } else {
-      ADD_FAILURE() << "Missing server connection";
-    }
+    ADD_FAILURE() << "Missing server connection";
   }
   server_thread_->Resume();
 
@@ -1763,15 +1750,8 @@
 
   QuicClientSessionCache* session_cache = static_cast<QuicClientSessionCache*>(
       client_crypto_config->mutable_session_cache());
-  std::string old_address_token;
-  if (GetQuicReloadableFlag(quic_tls_use_token_in_session_cache)) {
-    old_address_token =
-        QuicClientSessionCachePeer::GetToken(session_cache, server_id);
-  } else {
-    old_address_token =
-        client_crypto_config->LookupOrCreate(server_id)->source_address_token();
-  }
-  ASSERT_TRUE(!old_address_token.empty());
+  ASSERT_TRUE(
+      !QuicClientSessionCachePeer::GetToken(session_cache, server_id).empty());
 
   // Pause the server thread again to blackhole packets from client.
   server_thread_->Pause();
@@ -1779,17 +1759,9 @@
   EXPECT_FALSE(client_->client()->WaitForOneRttKeysAvailable());
   EXPECT_FALSE(client_->client()->connected());
 
-  std::string new_address_token;
-  if (GetQuicReloadableFlag(quic_tls_use_token_in_session_cache)) {
-    new_address_token =
-        QuicClientSessionCachePeer::GetToken(session_cache, server_id);
-    // Verify address token gets cleared.
-    ASSERT_TRUE(new_address_token.empty());
-  } else {
-    new_address_token =
-        client_crypto_config->LookupOrCreate(server_id)->source_address_token();
-    ASSERT_FALSE(new_address_token.empty());
-  }
+  // Verify address token gets cleared.
+  ASSERT_TRUE(
+      QuicClientSessionCachePeer::GetToken(session_cache, server_id).empty());
   server_thread_->Resume();
 }
 
diff --git a/quic/core/quic_dispatcher_test.cc b/quic/core/quic_dispatcher_test.cc
index add5164..2d5c78c 100644
--- a/quic/core/quic_dispatcher_test.cc
+++ b/quic/core/quic_dispatcher_test.cc
@@ -454,10 +454,6 @@
     ParsedClientHello parsed_chlo;
     parsed_chlo.alpns = {ExpectedAlpn()};
     parsed_chlo.sni = TestHostname();
-    if (address_token_.has_value() &&
-        !GetQuicReloadableFlag(quic_tls_use_token_in_session_cache)) {
-      parsed_chlo.retry_token = *address_token_;
-    }
     return parsed_chlo;
   }
 
diff --git a/quic/core/quic_flags_list.h b/quic/core/quic_flags_list.h
index 6dc0d06..7245004 100644
--- a/quic/core/quic_flags_list.h
+++ b/quic/core/quic_flags_list.h
@@ -101,8 +101,6 @@
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_server_reverse_validate_new_path3, true)
 // If true, when a packet is forced retransmitted, only set packet state if all data gets retransmitted.
 QUIC_FLAG(FLAGS_quic_restart_flag_quic_set_packet_state_if_all_data_retransmitted, true)
-// If true, when client attempts TLS resumption, use token in session_cache_ instead of cached_states_ in QuicCryptoClientConfig.
-QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_tls_use_token_in_session_cache, true)
 // When the flag is true, exit STARTUP after the same number of loss events as PROBE_UP.
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_bbr2_startup_probe_up_loss_events, true)
 // When true, defaults to BBR congestion control instead of Cubic.
diff --git a/quic/core/tls_client_handshaker.cc b/quic/core/tls_client_handshaker.cc
index 3cd47ad..d191017 100644
--- a/quic/core/tls_client_handshaker.cc
+++ b/quic/core/tls_client_handshaker.cc
@@ -42,13 +42,6 @@
       has_application_state_(has_application_state),
       crypto_config_(crypto_config),
       tls_connection_(crypto_config->ssl_ctx(), this, session->GetSSLConfig()) {
-  if (!GetQuicReloadableFlag(quic_tls_use_token_in_session_cache)) {
-    std::string token =
-        crypto_config->LookupOrCreate(server_id)->source_address_token();
-    if (!token.empty()) {
-      session->SetSourceAddressTokenToSend(token);
-    }
-  }
   if (crypto_config->tls_signature_algorithms().has_value()) {
     SSL_set1_sigalgs_list(ssl(),
                           crypto_config->tls_signature_algorithms()->c_str());
@@ -127,8 +120,7 @@
   }
   if (cached_state_) {
     SSL_set_session(ssl(), cached_state_->tls_session.get());
-    if (GetQuicReloadableFlag(quic_tls_use_token_in_session_cache) &&
-        !cached_state_->token.empty()) {
+    if (!cached_state_->token.empty()) {
       session()->SetSourceAddressTokenToSend(cached_state_->token);
     }
   }
@@ -435,14 +427,8 @@
   if (token.empty()) {
     return;
   }
-  if (GetQuicReloadableFlag(quic_tls_use_token_in_session_cache)) {
-    if (session_cache_ != nullptr) {
-      session_cache_->OnNewTokenReceived(server_id_, token);
-    }
-  } else {
-    QuicCryptoClientConfig::CachedState* cached =
-        crypto_config_->LookupOrCreate(server_id_);
-    cached->set_source_address_token(token);
+  if (session_cache_ != nullptr) {
+    session_cache_->OnNewTokenReceived(server_id_, token);
   }
 }