The BogonResolver relied on its wrapper resolver to pass along the
list of addresses _and_ the error. But the idiomatic thing to do is
often to return `nil` when there is an error.
I broke this very fragile assumption in https://github.com/ooni/probe-cli/pull/399.
I could of course fix it, but this assumption is clearly wrong
and we should not allow such fragile code in the tree.
We are not using BogonIsError much in the tree. The only place in
which we're using it for measuring seems to be dnscheck.
It may be that this surprising behavior was what caused the issue at
https://github.com/ooni/probe/issues/1510 in the first place.
Regardless, let's remove fragile code and adjust the test that was
failing. Also that test is quick so it can run in `-short` mode.
Spotted while working on https://github.com/ooni/probe/issues/1505.
This is how I did it:
1. `git clone https://github.com/ooni/probe-engine internal/engine`
2. ```
(cd internal/engine && git describe --tags)
v0.23.0
```
3. `nvim go.mod` (merging `go.mod` with `internal/engine/go.mod`
4. `rm -rf internal/.git internal/engine/go.{mod,sum}`
5. `git add internal/engine`
6. `find . -type f -name \*.go -exec sed -i 's@/ooni/probe-engine@/ooni/probe-cli/v3/internal/engine@g' {} \;`
7. `go build ./...` (passes)
8. `go test -race ./...` (temporary failure on RiseupVPN)
9. `go mod tidy`
10. this commit message
Once this piece of work is done, we can build a new version of `ooniprobe` that
is using `internal/engine` directly. We need to do more work to ensure all the
other functionality in `probe-engine` (e.g. making mobile packages) are still WAI.
Part of https://github.com/ooni/probe/issues/1335