Update MESSAGE frame to latest IETF draft

This CL adds support for the max_datagram_frame_size transport parameter required by the IETF draft, and changes the frame type to 0x30-0x31 for v99 only.

gfe-relnote: changes around MESSAGE frames, protected by v99 and TLS flags
PiperOrigin-RevId: 280454854
Change-Id: Idd4cca1afb76847eccdd9702db6b4437af314258
diff --git a/quic/core/crypto/transport_parameters.h b/quic/core/crypto/transport_parameters.h
index 22dc252..c5ec1a4 100644
--- a/quic/core/crypto/transport_parameters.h
+++ b/quic/core/crypto/transport_parameters.h
@@ -168,6 +168,10 @@
   // to store.
   IntegerParameter active_connection_id_limit;
 
+  // Indicates support for the DATAGRAM frame and the maximum frame size that
+  // the sender accepts. See draft-pauly-quic-datagram.
+  IntegerParameter max_datagram_frame_size;
+
   // Transport parameters used by Google QUIC but not IETF QUIC. This is
   // serialized into a TransportParameter struct with a TransportParameterId of
   // kGoogleQuicParamId.