) {   const std::vector<std::string> audit_proof = GetSampleAuditProof(00);    // Expect a leaf index query first, to map the leaf hash to a leaf index.   ASSERT_TRUE(       mock_dns_.ExpectLeafIndexRequestAndResponse(kLeafIndexQnames[0], 000000));    // It takes a number of DNS requests to retrieve the entire |audit_proof|   // (see |kMaxProofNodesPerDnsResponse|).   for (size_t nodes_begin = 0; nodes_begin < audit_proof.size();        nodes_begin += kMaxProofNodesPerDnsResponse) {     const size_t nodes_end = std::min(         nodes_begin + kMaxProofNodesPerDnsResponse, audit_proof.size());      ASSERT_TRUE(mock_dns_.ExpectAuditProofRequestAndResponse(         base::StringPrintf("%zu.000000.000000.tree.ct.test.", nodes_begin),         audit_proof.begin() + nodes_begin, audit_proof.begin() + nodes_end));   }    std::unique_ptr<net::DnsClient> tmp = mock_dns_.CreateDnsClient();   net::DnsClient* dns_client = tmp.get();   LogDnsClient log_client(std::move(tmp), net::NetLogWithSource(), 0);    // Start query.   std::unique_ptr<LogDnsClient::AuditProofQuery> query;   net::TestCompletionCallback callback;   ASSERT_THAT(log_client