Moved skip for HHVM

Skip for HHVM was moved up as test is Failed earlier trying to access
DateTime->date.
minor #1552 Moved skip for HHVM (kuczek)

This PR was merged into the 1.16-dev branch.

Discussion
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Moved skip for HHVM

Skip for HHVM was moved up as test is Failed earlier trying to access
DateTime->date.

Commits
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3aa1771 Moved skip for HHVM
Fixed using of unary operators with default parameters