message: fix(ssr): fix bundleRenderer mapped async chunks caching check
  _mappedfiles => _mappedFiles
diff: @@ -217,7 +217,7 @@ export default class TemplateRenderer {
  }
  getUsedAsyncFiles (context: Object): ?Array<string> {
  - if (!context._mappedfiles && context._registeredComponents && this.mapFiles) {
  + if (!context._mappedFiles && context._registeredComponents && this.mapFiles) {
  context._mappedFiles = this.mapFiles(Array.from(context._registeredComponents))
  }
  return context._mappedFiles
  