core: remove globals from externs.d.ts

[adamraine]

#14441 (comment)

• Global util types (SelfMap, Immutable, etc) are moved to util.d.ts and are accessible via LH.Util
• Global namespace modifications (Intl, Window) are moved to node.d.ts
• Any remaining external types (Flags, RunnerResult, etc) are staying in externs.d.ts

This is to separate global definitions only useful to us and non-global definitions we eventually want to expose.

[brendankenny]

Global util types (SelfMap, Immutable, etc) are moved to util.d.ts and are accessible via LH.Util

These seem like a prime subject for real imports instead of being in a new LH namespace. They're mostly used in d.ts files and they've never been namespaced before so no need to update existing usage. Some of the uses of them aren't needed as well...e.g. LH.Util.Immutable<LH.Config.Settings> should really just be LH.Audit.Context['settings'] in a lot (all?) of the updated cases.

[adamraine]

They're mostly used in d.ts files and they've never been namespaced before so no need to update existing usage.

Most of the usages I had to update were in .js files. Also importing these directly with jsdoc requires a template:

/**
 * @template T
 * @typedef {import('../types/util.js').default.SelfMap<T>} SelfMap
 */

e.g. LH.Util.Immutable<LH.Config.Settings> should really just be LH.Audit.Context['settings'] in a lot (all?) of the updated cases.

I'll try and update as many of these as I can.

[brendankenny]

wdyt about types/utility-types.d.ts? Even if redundant it self describes a little better and differentiates more from the four util.* files we already have

[adamraine]

Sure but still exposed as LH.Util?