Connection gating: adapt QUIC transport

[raulk]

Motivation

Now that #872 has landed, we have the abstractions and the hooks in the right places to actively intercept inbound and outbound connections at the following lifecycle stages:

• peer being dialled.
• address being dialled.
• connection being accepted.
• connection secured and authenticated.
• connection fully upgraded (or equivalent, i.e. we have a fully capable connection).

Transports that call the Upgrader are benefitting from the interception checkpoints automatically, but transports that support native crypto and multiplexing do not call the upgrader. One such example is QUIC.

For those cases, go-libp2p is now injecting the ConnectionGater to transports so we can manage connections at the very edges of system.

Goals

• Replace the *filter.Filters parameter in the QUIC transport constructor with connmgr.ConnectionGater, and call the right checkpoints at the right time.
  • note: for the sake of cleanliness, the Filters => ConnectionGater migration will be a breaking one, i.e. we have stopped injecting the *filter.Filters struct into constructors, so this adaption is totally necessary.

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This is a follow-up to #872.

[raulk]

@marten-seemann are you available to take this one? I'm happy to do it too.

[raulk]

Fixed by libp2p/go-libp2p-quic-transport#152.