src/vs/editor/standalone/browser/standaloneLanguages.ts/registerDocumentFormattingEditProvider
export function registerDocumentFormattingEditProvider(languageSelector: LanguageSelector, provider: languages.DocumentFormattingEditProvider): IDisposable {
	const languageFeaturesService = StandaloneServices.get(ILanguageFeaturesService);
	return languageFeaturesService.documentFormattingEditProvider.register(languageSelector, provider);
}