message: Fix segfault in grpc upstream log reporting.
  StreamInfoImpl::downstream_ssl_info_ was left uninitilaized
  in UpstreamRequest::stream_info_, and null check incorrectly
  passed for a pointer pointing nowhere.
  Risk Level: Low
  Testing: Surprisingly, all tests use NiceMock for StreamInfo which returns initialized null pointer :)
  Docs Changes: N/A
  Release Notes: N/A
diff: @@ -243,7 +243,7 @@ private:
  Network::Address::InstanceConstSharedPtr downstream_local_address_;
  Network::Address::InstanceConstSharedPtr downstream_direct_remote_address_;
  Network::Address::InstanceConstSharedPtr downstream_remote_address_;
  - const Ssl::ConnectionInfo* downstream_ssl_info_;
  + const Ssl::ConnectionInfo* downstream_ssl_info_{};
  std::string requested_server_name_;
  UpstreamTiming upstream_timing_;
  std::string upstream_transport_failure_reason_;
  