Description:
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The method ReflectionFunctionAbstract::getNumberOfRequiredParameters returns 1 for the method ReflectionClass::newInstance when it can be invoked with no parameter.

Furthermore I think the documentation should be updated because it is unclear if a parameter is required or not :
http://php.net/manual/en/reflectionclass.newinstance.php

FYI, HHVM returns already the right result : https://3v4l.org/RPXQp

Test script:
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<?php

$r = new ReflectionClass(ReflectionClass::class);
$m = $r->getMethod('newInstance');

echo $m->getNumberOfRequiredParameters(); // returns 1 instead of 0, KO



Expected result:
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0

Actual result:
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1