[automerger skipped] Support DNS64 synthesis using externally-discovered prefixes. am: 346737c0 am: fd0d47e2 -s ours

am skip reason: Change-Id I7c63fb62b70635a1b5cc7a21d60f091ba2705d72 with SHA-1 346737c0 is in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/modules/DnsResolver/+/11593902

Change-Id: I0a0b794d38b48accaddf346ba1e3c4c76e05f525