Moves QuicTag typedefs, and QuicTag utility methods to quic_tag.{h,cc}. No behavior change.

net/quic/core/crypto/quic_crypto_client_config.cc

Index: net/quic/core/crypto/quic_crypto_client_config.cc
diff --git a/net/quic/core/crypto/quic_crypto_client_config.cc b/net/quic/core/crypto/quic_crypto_client_config.cc
index b0bb2a356a6f17016027b5cfcfb8acf4b3bccfb0..d8d149fbe5863f13a02d7a67c9ffd0b3bdb8375c 100644
--- a/net/quic/core/crypto/quic_crypto_client_config.cc
+++ b/net/quic/core/crypto/quic_crypto_client_config.cc
@@ -532,11 +532,10 @@ QuicErrorCode QuicCryptoClientConfig::FillClientHello(
   // Key exchange: the client does more work than the server, so favor the
   // client's preference.
   size_t key_exchange_index;
-  if (!QuicUtils::FindMutualTag(aead, their_aeads, num_their_aeads,
-                                &out_params->aead, nullptr) ||
-      !QuicUtils::FindMutualTag(
-          kexs, their_key_exchanges, num_their_key_exchanges,
-          &out_params->key_exchange, &key_exchange_index)) {
+  if (!FindMutualQuicTag(aead, their_aeads, num_their_aeads, &out_params->aead,
+                         nullptr) ||
+      !FindMutualQuicTag(kexs, their_key_exchanges, num_their_key_exchanges,
+                         &out_params->key_exchange, &key_exchange_index)) {
     *error_details = "Unsupported AEAD or KEXS";
     return QUIC_CRYPTO_NO_SUPPORT;
   }
@@ -551,9 +550,8 @@ QuicErrorCode QuicCryptoClientConfig::FillClientHello(
       case QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND:
         break;
       case QUIC_NO_ERROR:
-        if (QuicUtils::FindMutualTag(
-                tb_key_params, their_tbkps, num_their_tbkps,
-                &out_params->token_binding_key_param, nullptr)) {
+        if (FindMutualQuicTag(tb_key_params, their_tbkps, num_their_tbkps,
+                              &out_params->token_binding_key_param, nullptr)) {
           out->SetVector(kTBKP,
                          QuicTagVector{out_params->token_binding_key_param});
         }