Make option and optgroup actually disabled inside disabled select

This PR makes option:disabled and optgroup:disabled match when either are inside disabled select elements, without changing the behavior of other algorithms like the selectedness setting algorithm when options are inside disabled selects. Also see w3c/csswg-drafts#13383

Author: josepharhar

source

@@ -57873,15 +57873,15 @@ interface <dfn interface>HTMLOptionElement</dfn> : <span>HTMLElement</span> {
   </div>
 
   <div algorithm>
-  <p>To get the <dfn><code>option</code> element nearest ancestor <code>select</code></dfn> given an
-  <code>option</code> <var>option</var>, run these steps. They return a <code>select</code> or
-  null.</p>
+  <p>To get the <dfn data-x="option element nearest ancestor select">nearest ancestor
+  <code>select</code></dfn> given an <code>Element</code> <var>element</var>, run these steps. They
+  return a <code>select</code> or null.</p>
 
   <ol>
    <li><p>Let <var>ancestorOptgroup</var> be null.</p></li>
 
    <li>
-    <p>For each <var>ancestor</var> of <var>option</var>'s <span data-x="ancestor">ancestors</span>,
+    <p>For each <var>ancestor</var> of <var>elements</var>'s <span data-x="ancestor">ancestors</span>,
     in reverse <span>tree order</span>:</p>
 
     <ol>
@@ -79597,9 +79597,14 @@ contradict people?
 
    <li>a <code>textarea</code> element that is <span data-x="concept-fe-disabled">disabled</span></li>
 
-   <li>an <code>optgroup</code> element that has a <code data-x="attr-optgroup-disabled">disabled</code> attribute</li>
+   <li>an <code>optgroup</code> element that has a <code
+   data-x="attr-optgroup-disabled">disabled</code> attribute or whose <span data-x="option element
+   nearest ancestor select">nearest ancestor <code>select</code></span> is <span
+   data-x="concept-fe-disabled">disabled</span></li>
 
-   <li>an <code>option</code> element that is <span data-x="concept-option-disabled">disabled</span></li>
+   <li>an <code>option</code> element that is <span data-x="concept-option-disabled">disabled</span>
+   or whose <span data-x="option element nearest ancestor select">nearest ancestor
+   <code>select</code></span> is <span data-x="concept-fe-disabled">disabled</span></li>
 
    <li>a <code>fieldset</code> element that is a <span data-x="concept-fieldset-disabled">disabled fieldset</span></li>