[OPENJPA-2668] fix for execution of a CriteriaQuery leaking into CriteriaQuery state

[michaelwiles]

for OPENJPA-2668
added copy method to Expressons.In and use that to return the expression
so that the original is not changed.

Not sure if there's a better way to do this. This is quite how can I say, simple?

This is the only Expression that I could find that dirties the original CriteriaQuery and I'm fairly convinced that this shouldn't happen.

Prior to this fix, executing the test would change the query and replace the parameter with the hydrated parameter values.

[ilgrosso]

Thanks @michaelwiles for your contribution.
Would you please adjust openjpa-persistence/src/main/java/org/apache/openjpa/persistence/criteria/Expressions.java so that only effective modifications are submitted? I see large changes due to formatting, ATM.

[michaelwiles]

hmmm... I'm going to create another pull request... this one is too broken to fix.

[michaelwiles]

remade here