Add a new connection option (BWS2) for an alternative bandwidth resumption experiment.

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 fa46608bda810edb27ff05943733846e71f1d320..28fe6d3873812d6f6b199543cfaca70ca9952bc8 100644
--- a/net/quic/core/crypto/crypto_protocol.h
+++ b/net/quic/core/crypto/crypto_protocol.h
@@ -121,6 +121,7 @@ const QuicTag kNCMR = TAG('N', 'C', 'M', 'R');   // Do not attempt connection
 const QuicTag kBWRE = TAG('B', 'W', 'R', 'E');  // Bandwidth resumption.
 const QuicTag kBWMX = TAG('B', 'W', 'M', 'X');  // Max bandwidth resumption.
 const QuicTag kBWRS = TAG('B', 'W', 'R', 'S');  // Server bandwidth resumption.
+const QuicTag kBWS2 = TAG('B', 'W', 'S', '2');  // Server bw resumption v2.
 
 // Enable path MTU discovery experiment.
 const QuicTag kMTUH = TAG('M', 'T', 'U', 'H');  // High-target MTU discovery.