src/vs/workbench/services/extensionManagement/browser/builtinExtensionsScannerService.ts/BuiltinExtensionsScannerService/_getBuiltinExtensionsUrl
class BuiltinExtensionsScannerService:	private _getBuiltinExtensionsUrl(environmentService: IWorkbenchEnvironmentService): URI | undefined {
		let enableBuiltinExtensions: boolean;
		if (environmentService.options && typeof environmentService.options._enableBuiltinExtensions !== 'undefined') {
			enableBuiltinExtensions = environmentService.options._enableBuiltinExtensions;
		} else {
			enableBuiltinExtensions = true;
		}
		if (enableBuiltinExtensions) {
			return FileAccess.asBrowserUri('../../../../../../extensions', require);
		}
		return undefined;
	}