Add support of serving SCT on the server side in QUIC, gated by QUIC_VERSION_30.

net/quic/quic_protocol.h

Index: net/quic/quic_protocol.h
diff --git a/net/quic/quic_protocol.h b/net/quic/quic_protocol.h
index 3db1304f8d092794f5d0284d3d5ec1cbf33b4a35..91ab6c28dc5ff285ed57e11c92db284d56451698 100644
--- a/net/quic/quic_protocol.h
+++ b/net/quic/quic_protocol.h
@@ -347,6 +347,7 @@ enum QuicVersion {
   QUIC_VERSION_27 = 27,  // Sends a nonce in the SHLO.
   QUIC_VERSION_28 = 28,  // Receiver can refuse to create a requested stream.
   QUIC_VERSION_29 = 29,  // Server and client honor QUIC_STREAM_NO_ERROR.
+  QUIC_VERSION_30 = 30,  // Add server side support of cert transparency.
 };
 
 // This vector contains QUIC versions which we currently support.
@@ -357,8 +358,8 @@ enum QuicVersion {
 // IMPORTANT: if you are adding to this list, follow the instructions at
 // http://sites/quic/adding-and-removing-versions
 static const QuicVersion kSupportedQuicVersions[] = {
-    QUIC_VERSION_29, QUIC_VERSION_28, QUIC_VERSION_27, QUIC_VERSION_26,
-    QUIC_VERSION_25};
+    QUIC_VERSION_30, QUIC_VERSION_29, QUIC_VERSION_28,
+    QUIC_VERSION_27, QUIC_VERSION_26, QUIC_VERSION_25};
 
 typedef std::vector<QuicVersion> QuicVersionVector;