Fixes the NullReferenceException in #1235 and appears to adhere to th…

…e practice of including an addres with the serialized binary.

src/core/Akka.Persistence/Serialization/MessageSerializer.cs

@@ -151,7 +151,7 @@ private Information GetTransportInformation()
             var address = system.Provider.DefaultAddress;
             return !string.IsNullOrEmpty(address.Host)
                 ? new Information { Address = address, System = system }
-                : null;
+                : new Information { System = system };
         }
     }
 }