Deprecate gfe2_reloadable_flag_quic_advance_ack_timeout_update.

PiperOrigin-RevId: 318076325
Change-Id: I06fe1c007d76fb56cf359d0ea7496bbbdae947df
diff --git a/quic/core/quic_connection_test.cc b/quic/core/quic_connection_test.cc
index 864a824..600c28a 100644
--- a/quic/core/quic_connection_test.cc
+++ b/quic/core/quic_connection_test.cc
@@ -10976,15 +10976,9 @@
   }));
   EXPECT_CALL(*send_algorithm_, OnPacketSent(_, _, _, _, _)).Times(1);
   ProcessDataPacket(1);
-  if (GetQuicReloadableFlag(quic_advance_ack_timeout_update)) {
-    // Verify ACK is bundled with WINDOW_UPDATE.
-    EXPECT_FALSE(writer_->ack_frames().empty());
-    EXPECT_FALSE(connection_.HasPendingAcks());
-  } else {
-    // ACK is pending.
-    EXPECT_TRUE(writer_->ack_frames().empty());
-    EXPECT_TRUE(connection_.HasPendingAcks());
-  }
+  // Verify ACK is bundled with WINDOW_UPDATE.
+  EXPECT_FALSE(writer_->ack_frames().empty());
+  EXPECT_FALSE(connection_.HasPendingAcks());
 }
 
 TEST_P(QuicConnectionTest, AckAlarmFiresEarly) {