Fixing broken tests

This reverts commit 8fc3387adc16f83f2b83ea4dfac25e9b6beb073d.
A filter adjusts the object that you pass it, the assertEquals method checks if all properties have the same values. 

If you remove the clone than this test will always pass and you won't be able to detect if anything has changed because the descriptor returns by the filter method will be the same instance as $descriptor