Make DiversificationNonce a std::array

net/quic/core/crypto/null_decrypter.cc

Index: net/quic/core/crypto/null_decrypter.cc
diff --git a/net/quic/core/crypto/null_decrypter.cc b/net/quic/core/crypto/null_decrypter.cc
index 132e93321d42778679ed3548ed49c37f9b10702f..dabbff59b463c9ad3b8929e9471940b4f723a496 100644
--- a/net/quic/core/crypto/null_decrypter.cc
+++ b/net/quic/core/crypto/null_decrypter.cc
@@ -30,7 +30,7 @@ bool NullDecrypter::SetPreliminaryKey(StringPiece key) {
   return false;
 }
 
-bool NullDecrypter::SetDiversificationNonce(DiversificationNonce nonce) {
+bool NullDecrypter::SetDiversificationNonce(const DiversificationNonce& nonce) {
   QUIC_BUG << "Should not be called";
   return true;
 }