gfe-relnote: In QUIC, rewrite part of QuicSession::OnStreamClosed to make it simpler. Refactoring only. No functional change expected. Protected by existing gfe2_reloadable_flag_quic_break_session_stream_close_loop.
gfe-relnote: In QUIC, rewrite part of QuicSession::OnStreamClosed to make it simpler. Refactoring only. No functional change expected. Protected by existing gfe2_reloadable_flag_quic_break_session_stream_close_loop.

PiperOrigin-RevId: 307101589
Change-Id: Ifc90bfebf0006814788897729a8b621cd3c7d3e9

google/quiche,google/quiche,google/quiche,google/quiche