eZ\Publish\Core\REST\Common\Output\Generator\Xml::startObjectElement PHP Method

    public function startObjectElement($name, $mediaTypeName = null)
    {
        $this->checkStartObjectElement($name);
        $this->isEmpty = false;
        $mediaTypeName = $mediaTypeName ?: $name;
        $this->xmlWriter->startElement($name);
        $this->startAttribute('media-type', $this->getMediaType($mediaTypeName));
        $this->endAttribute('media-type');
    }