Support datagrams in QuicTransport.

gfe-relnote: n/a (no functional change to production code)
PiperOrigin-RevId: 288493541
Change-Id: I6d2a791ae062701ad4b9fb650ab267566373675f

quic/core/quic_session.h

diff --git a/quic/core/quic_session.h b/quic/core/quic_session.h
index b818737..f10b548 100644
--- a/quic/core/quic_session.h
+++ b/quic/core/quic_session.h
@@ -19,6 +19,7 @@
 #include "net/third_party/quiche/src/quic/core/quic_connection.h"
 #include "net/third_party/quiche/src/quic/core/quic_control_frame_manager.h"
 #include "net/third_party/quiche/src/quic/core/quic_crypto_stream.h"
+#include "net/third_party/quiche/src/quic/core/quic_datagram_queue.h"
 #include "net/third_party/quiche/src/quic/core/quic_error_codes.h"
 #include "net/third_party/quiche/src/quic/core/quic_packet_creator.h"
 #include "net/third_party/quiche/src/quic/core/quic_packets.h"
@@ -616,6 +617,8 @@
     return stream_id_manager_;
   }
 
+  QuicDatagramQueue* datagram_queue() { return &datagram_queue_; }
+
   // Processes the stream type information of |pending| depending on
   // different kinds of sessions' own rules. Returns true if the pending stream
   // is converted into a normal stream.
@@ -788,6 +791,9 @@
   // Id of latest successfully sent message.
   QuicMessageId last_message_id_;
 
+  // The buffer used to queue the DATAGRAM frames.
+  QuicDatagramQueue datagram_queue_;
+
   // TODO(fayang): switch to linked_hash_set when chromium supports it. The bool
   // is not used here.
   // List of streams with pending retransmissions.