Forbidden (validation failure) sync errors

I've tested what I think will be quite a common case:

1. User gets an error because we're encoding the type in an inconsistent way with the sync_gateway schema.
2. We fix it in the frontend code
3. User clicks warning triangle
4. Model pushed, triangle disappears.

I have no reason to think it will be any different if step 2 is a fix on the sync_gateway side.