Add support for NumberFormatOptions notation

[benmccann]

Closes #36533

Adds the notation option to NumberFormatOptions in src/lib/es5.d.ts

I'm an experienced JS developer, but new to TypeScript, so if any changes are required to this PR you may have to give me some pointers.

[msftclas]

All CLA requirements met.

[NarasimhaReddyY]

This should be merged.

[benmccann]

Thanks for assigning this to yourself @sandersn. Any chance you'd be able to take a quick look? I'm hoping it should be an easy review since it's only a couple lines.

[sandersn]

I typically merge lib changes at the beginning of a version to let people find breaks, so I'll wait until 4.0 in a few weeks. Touching the ES5 lib is bound to break somebody, no matter how small the change.

[maneetgoyal]

@benmccann @awibox Should this property go in es5.d.ts or esnext.intl.d.ts instead?

I was just trying to draw some analogy with the Array object. All the common Array methods like forEach, map, etc. are in es5.d.ts. But the new ones like .flatMap and .flat are in es2019.array.d.ts.

notation recently became a standard property (right?). ECMAScript 2021 Intl specs (draft) makes a mention of it. No mention in ECMAScript 2019 Intl specs. So should it go in esnext.intl.d.ts/es2021.intl.d.ts instead of es5.d.ts?

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Edit: Just realizing, may be the location doesn't have anything to do ECMAScript and rather just depends upon browser support?

[BPScott]

Yo @sandersn, I'm guessing we've missed the boat for merging this and #38013 and we'll have to wait till the 4.1 cycle begins?

[sandersn]

Sorry for missing this. This should go into ES2020, not ES5, but if we can get it in before the beta on Monday it'll be fine to ship. I'm pretty sure the right place is es2020.intl.d.ts.

@benmccann I'll do it in the next day or so if I have time. I understand if you're sick of me forgetting about this. =)

[benmccann]

Great. Thanks so much @sandersn ! I'll leave the rest to you then. I'm pretty new to TypeScript, so I'm sure you have a much better handle on things than I do, but please let me know if there's anything I can do to help