reference-orientation treated as an inherited property

The "reference-orientation" property is currently treated as an inheritable property (see FOPropertMapping.createLayoutProperties()), but this is not defined as such in the XSL-FO 1.1 Recommendation (see: 7.21.3, http://www.w3.org/TR/xsl/#reference-orientation)

Simply changing the boolean in FOPropertyMapping reveals that we have somehow always worked around this issue. The generation of the region-reference-areas seems to depend on its 'reference-orientation % 90' being equal to that of the simple-page-master.

See for example:
RegionBody.getViewportRectangle() and Page.setRegionReferencePosition().