// Send Op, get ack.
channel.send(createAddParticipantOp());
assertEquals(1, waveViewService.submits.size());
WaveViewService.SubmitCallback submitCallback1 = waveViewService.lastSubmit().callback;
HashedVersion v2 = HashedVersion.of(2, SIGNATURE2);
submitCallback1.onSuccess(v2, 1, null, ResponseCode.OK);
assertUnsavedDataInfo(0, 1, 0, 2, 0);
// Send another Op, get ack.
channel.send(createAddParticipantOp());
assertEquals(2, waveViewService.submits.size());
WaveViewService.SubmitCallback submitCallback2 = waveViewService.lastSubmit().callback;
HashedVersion v3 = HashedVersion.of(3, SIGNATURE3);
submitCallback2.onSuccess(v3, 1, null, ResponseCode.OK);
assertUnsavedDataInfo(0, 2, 0, 3, 0);
// Server sends commit for the first addParticipant op.
openCallback.onUpdate(