Make QUIC tests restore flags to their default values

net/quic/chromium/quic_network_transaction_unittest.cc

Index: net/quic/chromium/quic_network_transaction_unittest.cc
diff --git a/net/quic/chromium/quic_network_transaction_unittest.cc b/net/quic/chromium/quic_network_transaction_unittest.cc
index 027b5ba61753755484dfa3621b139d7c41f503b2..1f6d4b65a3acb40e3b65ad6926323a58a3830b5b 100644
--- a/net/quic/chromium/quic_network_transaction_unittest.cc
+++ b/net/quic/chromium/quic_network_transaction_unittest.cc
@@ -2510,6 +2510,10 @@ TEST_P(QuicNetworkTransactionTest, QuicServerPush) {
 }
 
 TEST_P(QuicNetworkTransactionTest, QuicForceHolBlocking) {
+  ValueRestore<bool> old_v35_flag(&FLAGS_quic_enable_version_35,
+                                  FLAGS_quic_enable_version_35);
+  ValueRestore<bool> old_v36_flag(&FLAGS_quic_enable_version_36,
+                                  FLAGS_quic_enable_version_36);
   FLAGS_quic_enable_version_35 = true;
   FLAGS_quic_enable_version_36 = true;
   params_.quic_force_hol_blocking = true;