Add a default ON flag for DNS fail-fast feature am: 08422a0d am: 0397ef89 am: d0c719c9

Original change: https://android-review.googlesource.com/c/platform/packages/modules/DnsResolver/+/2821511



Change-Id: If2d8c1b9ef510c5071f0da93f617526f07bf9d22
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>