Add a transport socket config knob in quic_alia_transport_socket.proto to enable/disable early data.

QUICHE change only affects toy client.

PiperOrigin-RevId: 475290220
diff --git a/quiche/quic/tools/quic_toy_client.cc b/quiche/quic/tools/quic_toy_client.cc
index be51cf3..1c7cdaf 100644
--- a/quiche/quic/tools/quic_toy_client.cc
+++ b/quiche/quic/tools/quic_toy_client.cc
@@ -467,6 +467,8 @@
       }
       std::cout << "trailers: " << client->latest_response_trailers()
                 << std::endl;
+      std::cout << "early data accepted: " << client->EarlyDataAccepted()
+                << std::endl;
     }
 
     if (!client->connected()) {