fix(49869): No error in JavaScript on optional binding pattern parameter

[a-tarasyuk]

Fixes #49869

[voxpelli]

I think this caused a regression: voxpelli/pony-cause#45

I’ll check it better when I’m at a computer and will try to find time to post a proper issue about it.

[sandersn]

@a-tarasyuk looking at the failure, it's a question of whether we want to make Javascript syntax match Typescript syntax:
voxpelli/pony-cause#45 (comment)

[sandersn]

After thinking about it a bit, I think consistency with Typescript is more valuable than being able to be explicit about optionality of binding patterns in JSDoc. So currently I'd recommend leaving this fix as-is and changing pony-cause.

[voxpelli]

I disagree, but responded in voxpelli/pony-cause#45 (comment) rather than here so I won't repeat myself here :)

[voxpelli]

To ensure that this doesn't get lost, I added a proper regression report to the TS-repo: #50286