In quic, notify stream id manager stream close after connection disconnected. protected by gfe2_reloadable_flag_quic_notify_stream_id_manager_when_disconnected.

This is used to make DCHECK in chromium happy:https://cs.chromium.org/chromium/src/net/quic/quic_chromium_client_session.cc?rcl=f283ec21dadc7b21c7d98e317e227055bc5fe647&l=2981

PiperOrigin-RevId: 311771633
Change-Id: I45b771a20c79bee646f6caee85e8862a95899254

quic/core/quic_session.cc

diff --git a/quic/core/quic_session.cc b/quic/core/quic_session.cc
index 0f00ff3..033495f 100644
--- a/quic/core/quic_session.cc
+++ b/quic/core/quic_session.cc
@@ -1034,7 +1034,8 @@
     // Stream Id manager has been informed with draining streams.
     return;
   }
-  if (!connection_->connected()) {
+  if (!GetQuicReloadableFlag(quic_notify_stream_id_manager_when_disconnected) &&
+      !connection_->connected()) {
     // Do not bother informing stream ID manager if connection has been
     // disconnected.
     return;
@@ -1044,6 +1045,11 @@
     stream_id_manager_.OnStreamClosed(
         /*is_incoming=*/IsIncomingStream(stream_id));
   }
+  if (GetQuicReloadableFlag(quic_notify_stream_id_manager_when_disconnected) &&
+      !connection_->connected()) {
+    QUIC_RELOADABLE_FLAG_COUNT(quic_notify_stream_id_manager_when_disconnected);
+    return;
+  }
   if (IsIncomingStream(stream_id)) {
     // Stream Id manager is only interested in peer initiated stream IDs.
     if (VersionHasIetfQuicFrames(transport_version())) {