Switch FakeDns from List<String> to String[].

Currently this is a bit confusing because the inputs and the
synchronous path take String[], but the async path and the
futures take List<String>. Use String[] in both places.

This makes it easier to port to Kotlin as well.

Test: test-only change
Change-Id: I7d4ef6c1816778be4ce8ea4a5a6953c44e558990
2 files changed