[automerger skipped] Add PRIVATE_DNS_MODE setting setter am: 87ac58016f am: 43944db404 am: bce84c9a66 -s ours

am skip reason: skip tag Change-Id If234426f041606c4881de1eca31b6f5bdb3c6bfe with SHA-1 2832146318 is already in history

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1654014

Change-Id: I75eaedbfd00428cad87e5398c1f3bd54f0dbcd43