[automerger skipped] Fix use-after-free in DNS64 discovery thread am:...

[automerger skipped] Fix use-after-free in DNS64 discovery thread am: 292b59e1 am: 93d3a164 am: b1398479 -s ours am: 8e058e2c -s ours am: 655350de -s ours am: a75f039b -s ours am: c89d2d99 -s ours am: cf2fce39 -s ours am: 1caa098d -s ours am: 1541178e -s ours am: 758566b2 -s ours

am skip reason: Merged-In Id74ea4e6f54a00805d3cc8a9d7e15e58a473b7d3 with SHA-1 79f57106 is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/modules/DnsResolver/+/24557576



Change-Id: I5e1d6317fd6d1e13523fad4a04081ae1124befa4
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>