Upon receiving SETTINGS for a QuicSpdyClientSession, serialize the frame and cache it in tls_client_handshaker.

gfe-relnote: unused code. not protected.
PiperOrigin-RevId: 306897017
Change-Id: I94fbf706b7c9846befb80b1363a79dc022e95828
diff --git a/quic/core/tls_client_handshaker.cc b/quic/core/tls_client_handshaker.cc
index baac324..9e9e214 100644
--- a/quic/core/tls_client_handshaker.cc
+++ b/quic/core/tls_client_handshaker.cc
@@ -520,6 +520,11 @@
 void TlsClientHandshaker::OnApplicationState(
     std::unique_ptr<ApplicationState> application_state) {
   received_application_state_ = std::move(application_state);
+  if (session_cache_ != nullptr) {
+    // TODO(renjietang): cache the TLS session ticket and insert them together.
+    session_cache_->Insert(server_id_, nullptr, nullptr,
+                           received_application_state_.get());
+  }
 }
 
 }  // namespace quic