New NativeDaemonConnector protocol adds a seqnum.

Allows for one socket to be multiplexed for multiple requests.
Doesn't use command sequence numbers for broadcasts - would make no sense.
Doesn't alter current default behavior so OEM's using these classes
won't notice a difference.
bug:5864209

Change-Id: Ie3b19c4f81eea868569229a365c8cb7de249c2dd