[Filesystem] copy() is not working when open_basedir is set

More details: https://bugs.php.net/bug.php?id=64634
merged branch stloyd/patch-3 (PR #7869)

This PR was merged into the 2.1 branch.

Discussion
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[Filesystem] copy() is not working when open_basedir is set

More details: https://bugs.php.net/bug.php?id=64634

Commits
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10dea94 [Filesystem] copy() is not working when open_basedir is set