Now, MdnsServiceTypeClient is created using a network. However,
all tether interfaces use the same network (null), which
means they use the same client for the same service type. This is
not the intended behavior, as each interface should have its own
client. Therefore, MdnsServiceTypeClient creation should be
changed to use SocketKey, which includes both the network and
interface index. This will allow each interface to have its own
client.
Bug: 278018903
Test: atest FrameworksNetTests android.net.cts.NsdManagerTest
Change-Id: I34b7d983f00b67198befb5bf71fc511cf0dabae6
62b6439f96