Enable firefox CI job

[vasco-santos]

The firefox CI job was disabled, as a consequence of some inconsistencies between chrome and firefox tests for circuit ipfs/interop#62 https://travis-ci.com/ipfs/interop/builds/108339116.

After a small debugging session, the conclusions so far are the following:

Taking this test as an example of a failure: https://github.com/ipfs/interop/blob/master/test/circuit/browser.js#L103-L117 nodeB addresses are different in chrome and firefox

firefox:

['/p2p-circuit/ipfs/Qme9NFGddMSBQeQWkMEMJtnko9hA4pWhwPH9cJyteCkbyS', '/p2p-circuit/p2p-websocket-star/ipfs/Qme9NFGddMSBQeQWkMEMJtnko9hA4pWhwPH9cJyteCkbyS', '/p2p-websocket-star/ipfs/Qme9NFGddMSBQeQWkMEMJtnko9hA4pWhwPH9cJyteCkbyS']

chrome:

['/ip4/127.0.0.1/tcp/24642/ws/p2p-websocket-star/ipfs/Qmbmj7h1QzP7EW5xvssMZogM1RB4zs8JRf5d1XJmkJ71Er', '/p2p-circuit/ipfs/Qmbmj7h1QzP7EW5xvssMZogM1RB4zs8JRf5d1XJmkJ71Er', '/p2p-circuit/p2p-websocket-star/ipfs/Qmbmj7h1QzP7EW5xvssMZogM1RB4zs8JRf5d1XJmkJ71Er']

This way, when we do: getWsStarAddr(nodeB.addrs)m we will have /p2p-circuit/p2p-websocket-star/ipfs/Qme9NFGddMSBQeQWkMEMJtnko9hA4pWhwPH9cJyteCkbyS for firefox and /ip4/127.0.0.1/tcp/24642/ws/p2p-websocket-star/ipfs/Qmbmj7h1QzP7EW5xvssMZogM1RB4zs8JRf5d1XJmkJ71Er for chrome

After debugging in the switch, I got a weird behaviour. In firefox, the second dial arrives to the switch, but only with Circuit, no websocket-star, which then fails. In chrome, the second dial does nothing. Basically, even before starting the tests, there is an attempt of nodeB connecting nodeA, and they get connected before the connect in the test. I disabled discovery and bootstrap is empty, so is really odd

[jacobheun]

libp2p/js-peer-info#78 is the core reason this is failing. The circuit address and p2p-websocket-star address are treated as the same. The TCP address is removed from the p2p-websocket-star address at https://github.com/ipfs/js-ipfs/blob/v0.35.0/src/core/runtime/libp2p-browser.js#L21 for its listening purposes. Since neither address have ports, they're considered non distinct and p2p-circuit ends up winning.

libp2p/js-libp2p-switch#333 is the reason this passes on Chrome and not Firefox. The PR fixes the discrepancy in browser sorting.

cc: @alanshaw

[jacobheun]

Fixed in the latest switch build, master is passing now.