Examples: https://dvcs.w3.org/hg/pfwg/raw-file/default/ARIA/1.0/tests/test-files/roles-properties-supported-inherited/roles-properties-supported-inherited-columnheader-aria-readonly-true.html https://dvcs.w3.org/hg/pfwg/raw-file/default/ARIA/1.0/tests/test-files/roles-properties-supported-inherited/roles-properties-supported-inherited-columnheader-aria-readonly-false.html
<rdar://problem/13740854>
Related to bug 115123
…and bug 118364
Seems to be working now. RESOLVED/WORKSFORME.