QUIC - added code to read kUAID in the server code from the CHLO

net/quic/crypto/quic_crypto_server_config.cc

Index: net/quic/crypto/quic_crypto_server_config.cc
diff --git a/net/quic/crypto/quic_crypto_server_config.cc b/net/quic/crypto/quic_crypto_server_config.cc
index 52acd43ba9d1b8793f5fd03a128f50e8e88aa152..65db0f54878518cd3c4c6058b6f09d2242fecb92 100644
--- a/net/quic/crypto/quic_crypto_server_config.cc
+++ b/net/quic/crypto/quic_crypto_server_config.cc
@@ -80,6 +80,7 @@ struct ClientHelloInfo {
   StringPiece sni;
   StringPiece client_nonce;
   StringPiece server_nonce;
+  StringPiece user_agent_id;
 };
 
 struct ValidateClientHelloResultCallback::Result {
@@ -889,6 +890,8 @@ void QuicCryptoServerConfig::EvaluateClientHello(
     return;
   }
 
+  client_hello.GetStringPiece(kUAID, &info->user_agent_id);
+
   StringPiece srct;
   if (requested_config.get() != NULL &&
       client_hello.GetStringPiece(kSourceAddressTokenTag, &srct) &&