i18n: Use Intl.NumberFormat internally in i18n-calypso

[chriskmnds]

Fixes Automattic/i18n-issues#795
Related to #46564

Proposed Changes

• This refactors numberFormat method in i18n-calypso to utilise Intl.NumberFormat internally
• Introduces getBrowserSafeLocale method
• This should also fix the issue that the combination of number_fornat internally and Tannin may have introduced for HE locale (Automattic/i18n-issues#795)

Notes on approach/direction:

• See pxLjZ-9Eg-p2 for details on how we'll approach deprecation of numberFormat (or alternatively a general refactor around it)
• This is part one of a series of PRs, depending on whether we will keep the wrapper in the end or not.
• The signature changes have been kept minimal to not introduce more changes than needed to make the transition. In the next couple of follow-ups, the signature will be adapted to be a simple relay of Intl.NumberFormatOptions (and from there consider full deprecation or not). This is therefore an incremental change (in a way that best works for the author pursuing the refactor).

WIP: Additional details to follow.

Media

WIP

Why are these changes being made?

Fixes Automattic/i18n-issues#795
Related to https://href.li/?https://github.com/Automattic/wp-calypso/issues/46564

We only really need one way of formatting numbers in the codebase. Maybe one wrapper, or maybe one straight-up use of a vanilla API. Unless there is a good reason to not do so, we will pursue this path.

Testing Instructions

WIP

Pre-merge Checklist

• Has the general commit checklist been followed? (PCYsg-hS-p2)
• Have you written new tests for your changes?
• Have you tested the feature in Simple (P9HQHe-k8-p2), Atomic (P9HQHe-jW-p2), and self-hosted Jetpack sites (PCYsg-g6b-p2)?
• Have you checked for TypeScript, React or other console errors?
• Have you used memoizing on expensive computations? More info in Memoizing with create-selector and Using memoizing selectors and Our Approach to Data
• Have we added the "[Status] String Freeze" label as soon as any new strings were ready for translation (p4TIVU-5Jq-p2)?
  • For UI changes, have we tested the change in various languages (for example, ES, PT, FR, or DE)? The length of text and words vary significantly between languages.
• For changes affecting Jetpack: Have we added the "[Status] Needs Privacy Updates" label if this pull request changes what data or activity we track or use (p4TIVU-aUh-p2)?

[github-actions]

Calypso Live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-129843

Jetpack Cloud live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-129843&env=jetpack

Automattic for Agencies live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-129843&env=a8c-for-agencies

[matticbot]

Here is how your PR affects size of JS and CSS bundles shipped to the user's browser:

App Entrypoints (~417 bytes removed 📉 [gzipped])

name                   parsed_size           gzip_size
entry-subscriptions         -960 B  (-0.1%)     -417 B  (-0.1%)
entry-stepper               -960 B  (-0.1%)     -417 B  (-0.1%)
entry-main                  -960 B  (-0.0%)     -417 B  (-0.1%)
entry-login                 -960 B  (-0.0%)     -417 B  (-0.1%)
entry-domains-landing       -960 B  (-0.1%)     -417 B  (-0.2%)

Common code that is always downloaded and parsed every time the app is loaded, no matter which route is used.

Sections (~144 bytes removed 📉 [gzipped])

name                             parsed_size           gzip_size
reader                                -424 B  (-0.0%)      -68 B  (-0.0%)
plugins                               -424 B  (-0.0%)      -76 B  (-0.0%)
jetpack-cloud-plugin-management       -424 B  (-0.0%)      -76 B  (-0.0%)

Sections contain code specific for a given set of routes. Is downloaded and parsed only when a particular route is navigated to.

Async-loaded Components (~77 bytes removed 📉 [gzipped])

name                                              parsed_size           gzip_size
async-load-calypso-my-sites-stats-pages-insights       -424 B  (-0.7%)      -77 B  (-0.5%)

React components that are loaded lazily, when a certain part of UI is displayed for the first time.

Legend

What is parsed and gzip size?

Parsed Size: Uncompressed size of the JS and CSS files. This much code needs to be parsed and stored in memory.
Gzip Size: Compressed size of the JS and CSS files. This much data needs to be downloaded over network.

Generated by performance advisor bot at iscalypsofastyet.com.

[matticbot]

This PR modifies the release build for the following Calypso Apps:

For info about this notification, see here: PCYsg-OT6-p2

• blaze-dashboard
• command-palette-wp-admin
• happy-blocks
• help-center
• notifications
• odyssey-stats
• wpcom-block-editor

To test WordPress.com changes, run install-plugin.sh $pluginSlug update/i18n-deprecate-number-format-func on your sandbox.