gfe-relnote: In QUIC, do not send WINDOW_UPDATE if connection has been disconnected. Protected by ENABLED gfe2_reloadable_flag_quic_no_window_update_if_disconnected.

PiperOrigin-RevId: 297367843
Change-Id: Ia25263a5e449f1a02f5143248302a2403afb3653

quic/core/quic_flow_controller.cc

diff --git a/quic/core/quic_flow_controller.cc b/quic/core/quic_flow_controller.cc
index 7175a47..ccd3bfb 100644
--- a/quic/core/quic_flow_controller.cc
+++ b/quic/core/quic_flow_controller.cc
@@ -192,6 +192,11 @@
 }
 
 void QuicFlowController::MaybeSendWindowUpdate() {
+  if (GetQuicReloadableFlag(quic_no_window_update_if_disconnected) &&
+      !session_->connection()->connected()) {
+    QUIC_RELOADABLE_FLAG_COUNT(quic_no_window_update_if_disconnected);
+    return;
+  }
   // Send WindowUpdate to increase receive window if
   // (receive window offset - consumed bytes) < (max window / 2).
   // This is behaviour copied from SPDY.