Remove path id from IV in QUIC encrytion algorithms.

net/quic/core/crypto/aead_base_decrypter.cc

Index: net/quic/core/crypto/aead_base_decrypter.cc
diff --git a/net/quic/core/crypto/aead_base_decrypter.cc b/net/quic/core/crypto/aead_base_decrypter.cc
index 57984245c7a3f9bcc9bfb5f7ae5f32cc8022c4e0..08345dfda2a1d1e7c26e9b485b71ef897665d0a8 100644
--- a/net/quic/core/crypto/aead_base_decrypter.cc
+++ b/net/quic/core/crypto/aead_base_decrypter.cc
@@ -116,7 +116,6 @@ bool AeadBaseDecrypter::SetDiversificationNonce(
 }
 
 bool AeadBaseDecrypter::DecryptPacket(QuicVersion /*version*/,
-                                      QuicPathId path_id,
                                       QuicPacketNumber packet_number,
                                       StringPiece associated_data,
                                       StringPiece ciphertext,
@@ -135,10 +134,7 @@ bool AeadBaseDecrypter::DecryptPacket(QuicVersion /*version*/,
   uint8_t nonce[sizeof(nonce_prefix_) + sizeof(packet_number)];
   const size_t nonce_size = nonce_prefix_size_ + sizeof(packet_number);
   memcpy(nonce, nonce_prefix_, nonce_prefix_size_);
-  uint64_t path_id_packet_number =
-      QuicUtils::PackPathIdAndPacketNumber(path_id, packet_number);
-  memcpy(nonce + nonce_prefix_size_, &path_id_packet_number,
-         sizeof(path_id_packet_number));
+  memcpy(nonce + nonce_prefix_size_, &packet_number, sizeof(packet_number));
   if (!EVP_AEAD_CTX_open(
           ctx_.get(), reinterpret_cast<uint8_t*>(output), output_length,
           max_output_length, reinterpret_cast<const uint8_t*>(nonce),