In QuicSentPacketManager, rename enable_pto_ to pto_enabled_.

gfe-relnote: n/a (variable renaming)
PiperOrigin-RevId: 264889046
Change-Id: Ieb6b91511dc1d7bc5b68cf923f920205f010cd81
diff --git a/quic/core/quic_sent_packet_manager_test.cc b/quic/core/quic_sent_packet_manager_test.cc
index 8c2da38..fced1eb 100644
--- a/quic/core/quic_sent_packet_manager_test.cc
+++ b/quic/core/quic_sent_packet_manager_test.cc
@@ -368,7 +368,7 @@
     EXPECT_CALL(*send_algorithm_, SetFromConfig(_, _));
     EXPECT_CALL(*network_change_visitor_, OnCongestionChange());
     manager_.SetFromConfig(config);
-    EXPECT_TRUE(manager_.enable_pto());
+    EXPECT_TRUE(manager_.pto_enabled());
   }
 
   QuicSentPacketManager manager_;