Remove the non-RFC 7539 variants of ChaCha20Poly1305 crypters in QUIC

net/quic/crypto/quic_decrypter.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/quic/crypto/quic_decrypter.h"
 
 #include "net/quic/crypto/aes_128_gcm_12_decrypter.h"
-#include "net/quic/crypto/chacha20_poly1305_decrypter.h"
 #include "net/quic/crypto/chacha20_poly1305_rfc7539_decrypter.h"
 #include "net/quic/crypto/crypto_protocol.h"
 #include "net/quic/crypto/null_decrypter.h"
 
 namespace net {
 
 // static
 QuicDecrypter* QuicDecrypter::Create(QuicTag algorithm) {
   switch (algorithm) {
     case kAESG:
       return new Aes128Gcm12Decrypter();
-    case kCC12:
-      return new ChaCha20Poly1305Decrypter();
     case kCC20:
       return new ChaCha20Poly1305Rfc7539Decrypter();
     case kNULL:
       return new NullDecrypter();
     default:
       LOG(FATAL) << "Unsupported algorithm: " << algorithm;
       return nullptr;
   }
 }
 
 }  // namespace net