src/vs/editor/common/languages/languageConfigurationRegistry.ts/LanguageConfigurationRegistry/register
class LanguageConfigurationRegistry:	public register(languageId: string, configuration: LanguageConfiguration, priority: number = 0): IDisposable {
		let entries = this._entries.get(languageId);
		if (!entries) {
			entries = new ComposedLanguageConfiguration(languageId);
			this._entries.set(languageId, entries);
		}

		const disposable = entries.register(configuration, priority);
		this._onDidChange.fire(new LanguageConfigurationChangeEvent(languageId));

		return toDisposable(() => {
			disposable.dispose();
			this._onDidChange.fire(new LanguageConfigurationChangeEvent(languageId));
		});
	}