add aria-readonly canonical keyword

index.html

@@ -12687,7 +12687,7 @@ <h2>Definitions of States and Properties (all aria-* attributes)</h2>
 				</tbody>
 			</table>
 			<p>The attribute's <a data-cite="html/common-microsyntaxes.html#missing-value-default">missing value default</a> and <a data-cite="html/common-microsyntaxes.html#invalid-value-default">invalid value default</a> are both the False state.</p>
-
+			<p>For the purposes of <a data-cite="html/common-dom-interfaces.html#reflect">reflection</a>, the canonical keyword for the False state is the "false" keyword.</p>
 		</div>
 		<div class="property" id="aria-relevant">
 			<pdef>aria-relevant</pdef>