Remove path id from IV in QUIC encrytion algorithms.

net/quic/core/crypto/crypto_secret_boxer.cc

Index: net/quic/core/crypto/crypto_secret_boxer.cc
diff --git a/net/quic/core/crypto/crypto_secret_boxer.cc b/net/quic/core/crypto/crypto_secret_boxer.cc
index 15d0720e95c135d8f679eb09e24595adf57ef547..a1091524925dfa9d4d60e5a69c853d05f82e7c46 100644
--- a/net/quic/core/crypto/crypto_secret_boxer.cc
+++ b/net/quic/core/crypto/crypto_secret_boxer.cc
@@ -108,8 +108,7 @@ bool CryptoSecretBoxer::Unbox(StringPiece ciphertext,
     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)) {