"window is not defined" error comes from erizofc.js

[grokker001]

Description

I checked out from the master branch and trying to test the nodejs client. In the steps in the document, I have to import the built "erizofc.js" file. But when I tried to call

room = Erizo.Room(newIo, nativeConnectionHelpers, nativeConnectionManager, { token });

I got the following error:

2021-02-05 16:52:35.923 - INFO: ErizoSimpleNativeConnection - Getting token eyJ0b2tlbklkIjoiNjAxZGNjMzNlOGQ5ZmYxMjljNjRkMjA5IiwiaG9zdCI6ImxpY29kZS10ZXN0LnJ0Y2h1Yi5pbzo0NDMiLCJzZWN1cmUiOnRydWUsInNpZ25hdHVyZSI6Ik1HVXpPREV3TlRBeE9XVmhORFJrT1dFNE5tUTVNMk13TkRabFltTmhNbVpoWVRreU16aGlNQT09In0=
/home/user/projects/licode/spine/erizofc.js:7767
window.addEventListener('beforeunload', onBeforeUnload);
^

ReferenceError: window is not defined
at Socket (/home/user/projects/licode/spine/erizofc.js:7767:3)
at Object.Room (/home/user/projects/licode/spine/erizofc.js:3632:79)
at /home/user/projects/licode/spine/simpleNativeConnection.js:75:20
at exports.XMLHttpRequest.req.onreadystatechange (/home/user/projects/licode/spine/simpleNativeConnection.js:46:11)
at exports.XMLHttpRequest.dispatchEvent (/home/user/projects/licode/spine/node_modules/xmlhttprequest/lib/XMLHttpRequest.js:534:25)
at setState (/home/user/projects/licode/spine/node_modules/xmlhttprequest/lib/XMLHttpRequest.js:553:14)
at IncomingMessage. (/home/user/projects/licode/spine/node_modules/xmlhttprequest/lib/XMLHttpRequest.js:403:13)
at IncomingMessage.emit (events.js:215:7)
at endReadableNT (_stream_readable.js:1183:12)
at processTicksAndRejections (internal/process/task_queues.js:80:21)

Steps to reproduce the issue:

1. Build and install Licode from master branch
2. Start Licode and Basic example make sure Basic example works in the browser
3. Update /spine/spineClientsConfig.json file with the environment's setup
4. in /spine folder, run "node runSpineClients.js"

Describe the results you received:

ReferenceError: window is not defined

Describe the results you expected:

The test should process without errors. My understanding is if I want to run the nodejs client, there should be no global "window" object referred in the code, is it correct?

Additional environment details (Local, AWS, Docker, etc.):
Local