Deprecate gfe2_reloadable_flag_quic_fix_address_validation.

PiperOrigin-RevId: 345453566
Change-Id: Ifc0be33d6a5aff493f5bf314888d38c99e682dde
diff --git a/quic/core/quic_connection.cc b/quic/core/quic_connection.cc
index c8c4960..68c2d4a 100644
--- a/quic/core/quic_connection.cc
+++ b/quic/core/quic_connection.cc
@@ -1150,20 +1150,12 @@
                                        EncryptionLevel level) {
   last_decrypted_packet_level_ = level;
   last_packet_decrypted_ = true;
-  if (EnforceAntiAmplificationLimit()) {
-    bool address_validated =
-        last_decrypted_packet_level_ >= ENCRYPTION_HANDSHAKE;
-    if (GetQuicReloadableFlag(quic_fix_address_validation)) {
-      QUIC_RELOADABLE_FLAG_COUNT(quic_fix_address_validation);
-      address_validated =
-          (last_decrypted_packet_level_ == ENCRYPTION_HANDSHAKE ||
-           last_decrypted_packet_level_ == ENCRYPTION_FORWARD_SECURE);
-    }
-    if (address_validated) {
-      // Address is validated by successfully processing a HANDSHAKE or 1-RTT
-      // packet.
-      address_validated_ = true;
-    }
+  if (EnforceAntiAmplificationLimit() &&
+      (last_decrypted_packet_level_ == ENCRYPTION_HANDSHAKE ||
+       last_decrypted_packet_level_ == ENCRYPTION_FORWARD_SECURE)) {
+    // Address is validated by successfully processing a HANDSHAKE or 1-RTT
+    // packet.
+    address_validated_ = true;
   }
   idle_network_detector_.OnPacketReceived(time_of_last_received_packet_);
 
diff --git a/quic/core/quic_flags_list.h b/quic/core/quic_flags_list.h
index e21ad08..a19d821 100644
--- a/quic/core/quic_flags_list.h
+++ b/quic/core/quic_flags_list.h
@@ -37,7 +37,6 @@
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_enable_server_on_wire_ping, false)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_encrypted_control_frames, false)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_extract_x509_subject_using_certificate_view, true)
-QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_fix_address_validation, true)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_fix_arm_pto_for_application_data, true)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_fix_missing_initial_keys2, true)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_fix_out_of_order_sending2, true)