Description:
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XMLWriter::endElement() fails to emit a warning if too many parameters (= parameters at all) are passed. Gave me some trouble because I assumed it would write the ending tag of the specified tagname ("</$tagname>").

Reproduce code:
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<?php
header('Content-Type: text/xml; charset=utf-8');
$xml = new XMLWriter;
$xml->openMemory();
$xml->startDocument('1.0', 'UTF-8', 'yes');
$xml->writeComment('Generated by XMLWriter');
$xml->startElement('root');
$xml->writeElement('timestamp', time());
$xml->endElement('root'); // </root>
echo $xml->flush();
?>

Expected result:
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Warning: Wrong parameter count for XMLWriter::endElement() in %s on line %d

Actual result:
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No warning