net: use fake DNS dialer for /etc/hosts aliases tests
Change-Id: If9c41bd1e0497e76d901bfd2f749fbeb1ed3ac38
GitHub-Last-Rev:
f5777d8c20afb47b8cf093e43c7c25bbbb386e91
GitHub-Pull-Request: golang/go#61734
Reviewed-on: https://go-review.googlesource.com/c/go/+/515535
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Mateusz Poliwczak <mpoliwczak34@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>