/**
* Create 'staging' theme associated with current 'virtual' theme
*
* @return \Magento\Framework\View\Design\ThemeInterface
*/
protected function _createStagingTheme()
{
$stagingTheme = $this->_themeFactory->create();
$stagingTheme->setData(['parent_id' => $this->_theme->getId(), 'theme_path' => null, 'theme_title' => sprintf('%s - Staging', $this->_theme->getThemeTitle()), 'preview_image' => $this->_theme->getPreviewImage(), 'is_featured' => $this->_theme->getIsFeatured(), 'type' => \Magento\Framework\View\Design\ThemeInterface::TYPE_STAGING]);
$stagingTheme->save();
return $stagingTheme;
}