The previous implementation of writeLabels would not include a compressed name in the label dictionary, so if a packet had "something.local", "a.service.local" and "b.service.local", "service.local" would not be compressed because "a.service.local" already used compression (for .local). Fix this and add a test. Bug: 254166302 Test: atest Change-Id: I41c557d6debd11acb4c0813735ef7af7323f45d7