Support query cancellation for async DNS API

Bug: 124882626
Test: built, flashed, booted
      atest DnsResolverTest DnsPacketTest

Change-Id: Iaa72f5c17f58cf0a58663b892bb18cfdf23cd545
3 files changed
tree: 7de3fae233d9783f01e0a80418b3bfaad7809888
  1. core/
  2. services/
  3. tests/