Convert QUIC non-feature flags to the old syntax, for consistency.

net/quic/core/quic_version_manager.cc

Index: net/quic/core/quic_version_manager.cc
diff --git a/net/quic/core/quic_version_manager.cc b/net/quic/core/quic_version_manager.cc
index fb8bdf01ca04043e0df8a4a23c818d4c13040d20..7652813f858169a20d9f5f22a952f07997996099 100644
--- a/net/quic/core/quic_version_manager.cc
+++ b/net/quic/core/quic_version_manager.cc
@@ -10,7 +10,7 @@
 namespace net {
 
 QuicVersionManager::QuicVersionManager(QuicVersionVector supported_versions)
-    : enable_version_39_(GetQuicFlag(FLAGS_quic_enable_version_39)),
+    : enable_version_39_(FLAGS_quic_enable_version_39),
       enable_version_38_(FLAGS_quic_reloadable_flag_quic_enable_version_38),
       allowed_supported_versions_(supported_versions),
       filtered_supported_versions_(
@@ -24,9 +24,9 @@ const QuicVersionVector& QuicVersionManager::GetSupportedVersions() {
 }
 
 void QuicVersionManager::MaybeRefilterSupportedVersions() {
-  if (enable_version_39_ != GetQuicFlag(FLAGS_quic_enable_version_39) ||
+  if (enable_version_39_ != FLAGS_quic_enable_version_39 ||
       enable_version_38_ != FLAGS_quic_reloadable_flag_quic_enable_version_38) {
-    enable_version_39_ = GetQuicFlag(FLAGS_quic_enable_version_39);
+    enable_version_39_ = FLAGS_quic_enable_version_39;
     enable_version_38_ = FLAGS_quic_reloadable_flag_quic_enable_version_38;
     RefilterSupportedVersions();
   }