[Code Health] Delete unused code. am: aa510cee am: ebbb9411 am: af5e477c...

[Code Health] Delete unused code. am: aa510cee am: ebbb9411 am: af5e477c am: e51f754f am: bea79b74

Original change: https://android-review.googlesource.com/c/platform/packages/modules/DnsResolver/+/2746873



Change-Id: Ib4d15cb782d56c2f0478eb1e375312fe2b2284d7
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>