code: private void validateClosurePrimitive(Node n, JSDocInfo info) {
      if (info == null || !info.hasClosurePrimitiveId()) {
        return;
      }
  
      if (!isJSDocOnFunctionNode(n, info)) {
        report(n, MISPLACED_ANNOTATION, "closurePrimitive", "must be on a function node");
      }
    }
docs: Checks that a @closurePrimitive {id} is on a function