A PHPDoc result type of the \Magento\Framework\View\Element\UiComponent\ContentType\Html::render() method is wrong

https://github.com/magento/magento2/blob/c58d2d/lib/internal/Magento/Framework/View/Element/UiComponent/ContentType/Html.php#L15-L31

@return string is wrong because the $templateEngine variable could be an instance of the \Magento\Framework\View\TemplateEngine\Xhtml class, and its render() method returns an instance of the \Magento\Framework\View\TemplateEngine\Xhtml\ResultInterface (particularly, \Magento\Ui\TemplateEngine\Xhtml\Result), not a string:

https://github.com/magento/magento2/blob/c58d2d/lib/internal/Magento/Framework/View/TemplateEngine/Xhtml.php#L71-L89

https://github.com/magento/magento2/issues/3227

See also:

• The PHPDoc result type of the \Magento\Framework\View\TemplateEngineInterface::render() method is wrong
• The PHPDoc result type of the \Magento\Ui\Component\AbstractComponent::render() method is wrong