Make sure HttpNetworkSession::Params::allow_default_credentials is initialized

Initialize allow_default_credentials before being used in HttpNetworkSession::QuicInfoToValue(), as this can cause a use-of-uninitialized-value in net::FileNetLogObserver::FileWriter::WritePolledDataToFile, where in JSONWriter::BuildJSONString, for Value::Type::BOOLEAN, node.GetBool() contains an uninitialized value.

Change-Id: Ia3c1f530046c246255cde9394b04773eb5d9ccac
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1853991
Commit-Queue: Asanka Herath <asanka@chromium.org>
Reviewed-by: Asanka Herath <asanka@chromium.org>
Cr-Commit-Position: refs/heads/master@{#705284}

net/http/http_network_session.cc

@@ -87,7 +87,9 @@ HttpNetworkSession::Params::Params()
       enable_websocket_over_http2(false),
       enable_quic(false),
       enable_quic_proxies_for_https_urls(false),
-      disable_idle_sockets_close_on_memory_pressure(false) {
+      disable_idle_sockets_close_on_memory_pressure(false),
+      allow_default_credentials(HttpAuthPreferences::DefaultCredentials::
+                                    DISALLOW_DEFAULT_CREDENTIALS) {
   enable_early_data =
       base::FeatureList::IsEnabled(features::kEnableTLS13EarlyData);
 }