Instead of creating one NetworkInterfaceProvider for each MdnsSocket,
create one in MdnsSocketClient and use it for each MdnsSocket.
MdnsSocket only calls getMulticastNetworkInterfaces and
getAvailableNetwork on MulticastNetworkInterfaceProvider, which are
thread-safe (the first one is synchronized). There is no need to have
multiple MulticastNetworkInterfaceProvider tracking the same state.
This allows reducing the number of callbacks filed to
ConnectivityManager, which is a resource usage improvement and can be
beneficial for huge apps that have many components which may
collectively reach the MAX_NETWORK_REQUESTS_PER_UID limit in
ConnectivityService (100).
MdnsSocketClient is unused in AOSP so this is a no-op in the platform.
It is only used by users of the unbundled mdns library.
Bug: 322049918
Test: atest
Change-Id: I515459beaee6aacc99c7c0c2a05c3c9c41473b62
0a9dbc9d12