2. Modified several of our sample and test FO files to be compliant with the XSL spec with respect to the change above.
3. @todo's added to FO's still missing validateChildNode()
4. New FONode missingPropertyError() method created, for the major cases where missing properties should halt processing.
5. Various cleanup in our layout-master-set and region classes, including the removal of error checks that are no longer needed due to validateChildNode() being implemented.
git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@197889 13f79535-47bb-0310-9956-ffa450edef68
