Allow to define section frontend model in system configuration

[ytorbyk]

There is ability to define/use custom block (frontend model) for system configuration section node in code. See \Magento\Config\Block\System\Config\Edit::_prepareLayout() method. But appropriate nodes are absent in system.xsd and system_file.xsd.

[magento-cicd2]

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[ytorbyk]

What should I do this pull request has been merged?
I really need this feature, I use it in my extension.

[dsikkema-magento]

the attribute group for this element is defined on line 55, would it make more sense to put it there?

[ytorbyk]

I guess no. It will add the attribute for <group> node.
But I've added new element/node inside <section> node. It is used in this function
\Magento\Config\Block\System\Config\Edit::_prepareLayout()

protected function _prepareLayout()
{
/** @var $section \Magento\Config\Model\Config\Structure\Element\Section */
$section = $this->_configStructure->getElement($this->getRequest()->getParam('section'));
$this->_formBlockName = $section->getFrontendModel();
if (empty($this->_formBlockName)) {
$this->_formBlockName = self::DEFAULT_SECTION_BLOCK;
}
...
}
And the node allows to use custom block for section rendering.

[dsikkema-magento]

Internal ticket: MAGETWO-49794