Description:
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Hi,

Calling iterator_count() is affecting RecursiveDirectoryIterator::valid() and RecursiveDirectoryIterator::valid() is returning false after iterator_count() call.

I am not sure that is a bug or just a behavior of PHP, but simply looks weird invalidating it without any iteration act such as while or foreach.

Test script:
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$iter = new RecursiveDirectoryIterator("/tmp/", RecursiveDirectoryIterator::SKIP_DOTS);
var_dump($iter->valid());
var_dump(iterator_count($iter));
var_dump($iter->valid());

Expected result:
----------------
bool(true)
int(24)
bool(true)

Actual result:
--------------
bool(true)
int(24)
bool(false)