Use dynamic receive window sizes in Hyperloop.

Protected by FLAGS_gfe2_restart_flag_track_hyperloop_streams3.

PiperOrigin-RevId: 745298399

quiche/quic/core/quic_session.cc

diff --git a/quiche/quic/core/quic_session.cc b/quiche/quic/core/quic_session.cc
index 26a1eae..6e79b25 100644
--- a/quiche/quic/core/quic_session.cc
+++ b/quiche/quic/core/quic_session.cc
@@ -704,6 +704,7 @@
 }
 
 void QuicSession::OnBlockedFrame(const QuicBlockedFrame& frame) {
+  QUIC_CODE_COUNT(quic_session_blocked_frame_received);
   // TODO(rjshade): Compare our flow control receive windows for specified
   //                streams: if we have a large window then maybe something
   //                had gone wrong with the flow control accounting.