44449e29d2
This adds some custom code for serialising ResponseMessage to ensure that only one of result or error are ever specified, as required by JSON RPC. Change-Id: I2736b83755553a906264b1e5251d1a535dc289fb Reviewed-on: https://dart-review.googlesource.com/c/88953 Reviewed-by: Brian Wilkerson <brianwilkerson@google.com> Commit-Queue: Danny Tuppeny <dantup@google.com>