Fix unit tests for PHP >= 5.4.29 or >= 5.5.13
minor #352 Fix unit tests for PHP >= 5.4.29 or >= 5.5.13 (hlubek)

This PR was merged into the 0.4.x-dev branch.

Discussion
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Fix unit tests for PHP >= 5.4.29 or >= 5.5.13

Fix for #351

Fixes the unit tests when running on the PHP versions that changed the serialization behavior. There's no way to mock internal classes without calling the constructor, so the easiest fix is to use an actual instance of SplFileInfo instead of using a mock.

Commits
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bf4ef50 Fix unit tests for PHP >= 5.4.29 or >= 5.5.13