This is, perhaps, the trival final piece of #7075 that I've been
working on.
There's more work to be done:
- push more of the setup into the pacakges themselves
- move channel-based sending/filtering out of the
- simplify the buffering throuhgout the p2p stack.
This changes adds a failing test for issue #6660. It achieves this by adding a transaction, starting the `broadcastTxRoutine` in a goroutine and then adding another transaction to the mempool. The `broadcastTxRoutine` can receive the second inserted transaction before `insertTx` returns. In that case, `broadcastTxRoutine` will derefence a nil pointer when referencing the `gossipEl` and panic.
Sam Kleinman
William Banfield