code: function applyClassDecorators(classPath) {
    if (!hasClassDecorators(classPath.node)) return;
  
    const decorators = classPath.node.decorators || [];
    classPath.node.decorators = null;
  
    const name = classPath.scope.generateDeclaredUidIdentifier("class");
  
    return decorators
      .map(dec => dec.expression)
      .reverse()
      .reduce(function(acc, decorator) {
        return buildClassDecorator({
          CLASS_REF: t.cloneNode(name),
          DECORATOR: t.cloneNode(decorator),
          INNER: acc,
        }).expression;
      }, classPath.node);
  }
docs: Given a class expression with class-level decorators, create a new expression
  with the proper decorated behavior.