Adds an internal server and chromium's flag for disabling/enabling FEC

net/quic/quic_client_session_base.cc

Index: net/quic/quic_client_session_base.cc
diff --git a/net/quic/quic_client_session_base.cc b/net/quic/quic_client_session_base.cc
index 4343011437e44e42ea2eec075ecd03e258044ac6..40d4b86dc2cb46e439152a60a0958a0806b41038 100644
--- a/net/quic/quic_client_session_base.cc
+++ b/net/quic/quic_client_session_base.cc
@@ -4,6 +4,8 @@
 
 #include "net/quic/quic_client_session_base.h"
 
+#include "net/quic/quic_flags.h"
+
 namespace net {
 
 QuicClientSessionBase::QuicClientSessionBase(
@@ -13,4 +15,19 @@ QuicClientSessionBase::QuicClientSessionBase(
 
 QuicClientSessionBase::~QuicClientSessionBase() {}
 
+void QuicClientSessionBase::OnCryptoHandshakeEvent(CryptoHandshakeEvent event) {
+  QuicSession::OnCryptoHandshakeEvent(event);
+  // Set FEC policy for streams immediately after sending CHLO and before any
+  // more data is sent.
+  if (!FLAGS_enable_quic_fec ||
+      event != ENCRYPTION_FIRST_ESTABLISHED ||
+      !config()->HasSendConnectionOptions() ||
+      !ContainsQuicTag(config()->SendConnectionOptions(), kFHDR)) {
+    return;
+  }
+  // kFHDR config maps to FEC protection always for headers stream.
+  // TODO(jri): Add crypto stream in addition to headers for kHDR.
+  headers_stream_->set_fec_policy(FEC_PROTECT_ALWAYS);
+}
+
 }  // namespace net