Tests that it's okay to unregister the event listener while handling the event.

On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".

PASS connection.type is newConnectionType
PASS connection.downlinkMax is newDownlinkMax
PASS connection.effectiveType is initialEffectiveType
PASS connection.rtt is initialRtt
PASS connection.downlink is initialDownlink
PASS connection.type is initialType
PASS connection.downlinkMax is initialDownlinkMax
PASS connection.effectiveType is initialEffectiveType
PASS connection.rtt is initialRtt
PASS connection.downlink is initialDownlink
PASS successfullyParsed is true

TEST COMPLETE