QuicSession no longer directly owns its QuicConnection. Not flag protected.

net/quic/core/quic_client_session_base.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/quic/core/quic_client_session_base.h"
 
 #include "net/quic/core/quic_client_promised_info.h"
 #include "net/quic/core/quic_flags.h"
 #include "net/quic/core/spdy_utils.h"
 
 using base::StringPiece;
 using std::string;
 
 namespace net {
 
 QuicClientSessionBase::QuicClientSessionBase(
     QuicConnection* connection,
     QuicClientPushPromiseIndex* push_promise_index,
     const QuicConfig& config)
     : QuicSpdySession(connection, config),
       push_promise_index_(push_promise_index),
       largest_promised_stream_id_(kInvalidStreamId) {}
 
 QuicClientSessionBase::~QuicClientSessionBase() {
   //  all promised streams for this session
   for (auto& it : promised_by_id_) {
     DVLOG(1) << "erase stream " << it.first << " url " << it.second->url();
     push_promise_index_->promised_by_url()->erase(it.second->url());
   }
+  delete connection();
 }
 
 void QuicClientSessionBase::OnConfigNegotiated() {
   QuicSpdySession::OnConfigNegotiated();
 }
 
 void QuicClientSessionBase::OnCryptoHandshakeEvent(CryptoHandshakeEvent event) {
   QuicSession::OnCryptoHandshakeEvent(event);
 }
 
@@ skipping 156 matching lines @@
 void QuicClientSessionBase::ResetPromised(QuicStreamId id,
                                           QuicRstStreamErrorCode error_code) {
   SendRstStream(id, error_code, 0);
   if (!IsOpenStream(id)) {
     MaybeIncreaseLargestPeerStreamId(id);
     InsertLocallyClosedStreamsHighestOffset(id, 0);
   }
 }
 
 }  // namespace net