code: protected ExpressionNode getExpressionOwner(ExpressionNode ex)
    {
    	ExpressionNode parent = ex.exprGetParent();
    	while((null != parent) && (parent instanceof Expression))
    		parent = parent.exprGetParent();
    	return parent;
    }
docs: Get the first non-Expression parent of this node.
  @return null or first ancestor that is not an Expression.