Drop packets shorter than the stateless reset length.

Protected by FLAGS_quic_reloadable_flag_quic_stateless_reset.

PiperOrigin-RevId: 358952649
Change-Id: I0b22fcf3912fd77d6872afdb2f3343dfe004d9ff

quic/core/quic_flags_list.h

diff --git a/quic/core/quic_flags_list.h b/quic/core/quic_flags_list.h
index 97930ff..a3bc225 100644
--- a/quic/core/quic_flags_list.h
+++ b/quic/core/quic_flags_list.h
@@ -56,6 +56,7 @@
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_server_reverse_validate_new_path, false)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_single_ack_in_packet2, false)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_start_peer_migration_earlier, true)
+QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_stateless_reset, true)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_stateless_reset_faster_random, false)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_testonly_default_false, false)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_testonly_default_true, true)