list > group > listitem should not be allowed

[WilcoFiers]

As of WAI-ARIA 1.2, groups are no longer allowed in lists. This is soon changing in ACT as well. We should make sure the following fails axe-core:

<div role="list">
  <div role="group">
    <div role="listitem">list item</div>
  </div>
</div>

To fix this, remove group from list and listitem in standards/aria-roles.js, and fix any tests that fail.

[WilcoFiers]

This was done a while back. Needs QA though.

[padmavemulapati]

Validated with the latest axe-core develop branch code base,

role=group are no longer allowed inside lists and listitems.
Test snippet:

 <div role="list" id="target"><ul role="group"><li role="listitem">Item</li></ul></div>

aria-required-children should fail here as this is holding role=group as child for role=list.

Also:
Require aria-controls on combobox.
Require focusable separators to have aria-value now.
Require combobox, radio, seperator now require aria-checked. The default value of false is no longer assumed.
Test snippet:

<!--aria-req-parent should pass here-->
   <div role="tree"><div role="none"><div role="group"><div role="none"><div role="group"><div role="treeitem" id="target">Nothing here.</div></div></div></div></div></div>
   <!--aria-req-attr should fail when role=seperator--> 
   <span role="radio" id="aratrr_fail">I am BLUE!</span>
<div role="separator" id="violation" tabindex="0"></div>
<div id="target-fail" role="combobox" aria-expanded="invalid-value"></div>