Exception thrown in Torrent._debug after torrent has been destroyed.

[jsdt]

What version of this package are you using?

0.107.17

What operating system, Node.js, and npm version?

I'm using Node 10 in App Engine.

What happened?

I've seen some exceptions in the logs which appear to come from calling _debug on a torrent that has already been destroyed. The stack trace is posted below.

TypeError: Cannot read property '_debugId' of null
    at Torrent._debug (/srv/node_modules/webtorrent/lib/torrent.js:1633:31)
    at utPex.wire.ut_pex.on.peer (/srv/node_modules/webtorrent/lib/torrent.js:982:14)
    at utPex.emit (events.js:198:13)
    at compact2string.multi.forEach.peer (/srv/node_modules/ut_pex/index.js:107:18)
    at Array.forEach (<anonymous>)
    at utPex.onMessage (/srv/node_modules/ut_pex/index.js:103:45)
    at Wire._onExtended (/srv/node_modules/bittorrent-protocol/index.js:554:26)
    at Wire._onMessage (/srv/node_modules/bittorrent-protocol/index.js:686:21)
    at Wire._write (/srv/node_modules/bittorrent-protocol/index.js:590:12)
    at doWrite (/srv/node_modules/readable-stream/lib/_stream_writable.js:405:139)
    at writeOrBuffer (/srv/node_modules/readable-stream/lib/_stream_writable.js:394:5)
    at Wire.Writable.write (/srv/node_modules/readable-stream/lib/_stream_writable.js:303:11)
    at Socket.ondata (_stream_readable.js:709:20)
    at Socket.emit (events.js:198:13)
    at addChunk (_stream_readable.js:288:12)
    at readableAddChunk (_stream_readable.js:269:11)
    at Socket.Readable.push (_stream_readable.js:224:10)
    at TCP.onStreamRead (internal/stream_base_commons.js:94:17)

What did you expect to happen?

I didn't expect an exception.

Are you willing to submit a pull request to fix this bug?

Sure. I can submit a fix that skips logging if the client has already been wiped out, but I wanted to check if some other change would make more sense.

[jsdt]

This was fixed in #1801