DE53956 Replace optional chaining syntax for compatibility with Polymer

[mostlyfabulous]

DE53956: [WCAG2.2] Activity Feed > Several buttons with enclosed focus not meeting Focus appearance requirements

We haven't managed to move away from Polymer yet: https://github.com/Brightspace/assignments-ui/pull/323#issuecomment-1631896201

[github-actions]

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[svanherk]

We've definitely started using optional chaining in a number of places across core, this might not be the only spot that's an issue. It's actually not a Polymer problem, just a polymer-cli problem because it's so old and not updated/maintained. Is it only polymer lint that's failing for you? Or does the polymer test command fail too?

[dlockhart]

Yeah recently when we've been running into this, we've started switching repos off polymer lint entirely and converting polymer test uses over to the more modern @web/test-runner. You're going to run into a lot more than core using modern JS these days.

[mostlyfabulous]

It fails on polymer lint. I can't run polymer test locally anymore 😅- getting errors now when I try.
We've got the De-FRA on the backlog, but I'm not sure when we'll fully be able to start on it.

[mostlyfabulous]

Would you recommend we just remove polymer lint for now as optional chaining will work otherwise?

[dlockhart]

Yep, just remove it.