Add connection option kSMHL indicating supporting SETTINGS_MAX_HEADER_LIST_SIZE. SETTINGS_MAX_HEADE…

net/quic/core/crypto/crypto_protocol.h

Index: net/quic/core/crypto/crypto_protocol.h
diff --git a/net/quic/core/crypto/crypto_protocol.h b/net/quic/core/crypto/crypto_protocol.h
index 2d3a6b8b18cbed79ff46c3f2dd121547325114ec..975bdb51fcdd1f0770487e3ccee0ecbb3ab81a63 100644
--- a/net/quic/core/crypto/crypto_protocol.h
+++ b/net/quic/core/crypto/crypto_protocol.h
@@ -107,6 +107,10 @@ const QuicTag kCONH = TAG('C', 'O', 'N', 'H');   // Conservative Handshake
                                                  // Retransmissions.
 const QuicTag kLFAK = TAG('L', 'F', 'A', 'K');   // Don't invoke FACK on the
                                                  // first ack.
+// TODO(fayang): Remove this connection option in QUIC_VERSION_37, in which
+// MAX_HEADER_LIST_SIZE settings frame should be supported.
+const QuicTag kSMHL = TAG('S', 'M', 'H', 'L');   // Support MAX_HEADER_LIST_SIZE
+                                                 // settings frame.
 
 // Optional support of truncated Connection IDs.  If sent by a peer, the value
 // is the minimum number of bytes allowed for the connection ID sent to the