[eclipselink-dev] Fix for bug 378512 checked in

[David Minsky <david.minsky@xxxxxxxxxx>]

Bug 378512 - IllegalArgumentException occurs during mergeChanges when using nested UoW with inheritance tree
https://bugs.eclipse.org/bugs/show_bug.cgi?id=378512

- Changed code in MergeManager mergeChangesOfWorkingCopyIntoOriginal(Object clone, ObjectChangeSet objectChangeSet) to explicitly pass the the correct original version of a new object (specifically from a nested UnitOfWork) into the registerOriginalNewObjectFromNestedUnitOfWork() call
- Added regression test: NestedUnitOfWorkMergeIntoParentTest to: InheritanceTestModel with new test model classes Apple, Fruit, Pear, Teacher
- Small changes to CommitOrderTest to support new model classes

Testing: Core LRG & JPA LRG (ok)

Checked into trunk (2.4) at revision: 11279
Reviewed: Guy
2.3.x checkin pending