message: fix(renderer): remove unnecessary exported function
diff: @@ -37,10 +37,6 @@ export function isContentView(view: any): view is NgContentView {
  return view instanceof ContentView;
  }
  -export function isPlaceholder(view: any): view is NgPlaceholder {
  - return view instanceof Placeholder;
  -}
  -
  const propertyMaps: Map<Function, Map<string, string>> = new Map<Function, Map<string, string>>();
  export class ViewUtil {
  