return new RefactoringDescriptorDiff((RefactoringDescriptorProxy) element, getKind(element), getDirection(element));
return new RefactoringHistoryDiff((RefactoringHistory) element, getKind(element), getDirection(element));
	protected IDiffNode getDiff(final Object element) {		if (element instanceof RefactoringDescriptorProxy)			return new RefactoringDescriptorDiff((RefactoringDescriptorProxy) element, getKind(element), getDirection(element));		else if (element instanceof RefactoringHistory)			return new RefactoringDescriptorDiff((RefactoringDescriptorProxy) element, getKind(element), getDirection(element));		return super.getDiff(element);	}