Remove path id from IV in QUIC encrytion algorithms.

net/quic/core/crypto/crypto_secret_boxer.cc

 // Copyright (c) 2013 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/core/crypto/crypto_secret_boxer.h"
 
 #include <memory>
 
 #include "base/logging.h"
 #include "net/quic/core/crypto/aes_128_gcm_12_decrypter.h"
@@ skipping 90 matching lines @@
 
   std::unique_ptr<Aes128Gcm12Decrypter> decrypter(new Aes128Gcm12Decrypter());
   char plaintext[kMaxPacketSize];
   size_t plaintext_length = 0;
   bool ok = false;
   {
     QuicReaderMutexLock l(&lock_);
     for (const string& key : keys_) {
       if (decrypter->SetKey(key)) {
         decrypter->SetNoncePrefix(nonce_prefix);
-        if (decrypter->DecryptPacket(QUIC_VERSION_36,
-                                     /*path_id=*/0u, packet_number,
+        if (decrypter->DecryptPacket(QUIC_VERSION_36, packet_number,
                                      /*associated data=*/StringPiece(),
                                      ciphertext, plaintext, &plaintext_length,
                                      kMaxPacketSize)) {
           ok = true;
           break;
         }
       }
     }
   }
   if (!ok) {
     return false;
   }
 
   out_storage->resize(plaintext_length);
   out_storage->assign(plaintext, plaintext_length);
   out->set(out_storage->data(), plaintext_length);
   return true;
 }
 
 }  // namespace net