"suggestion" role is not aligned with "Allowed Accessibility Child Roles" model

[giacomo-petri]

We moved from "Required Owned Elements" to "Allowed Accessibility Child Roles", updating all related roles accordingly. However, the definition for suggestion still appears somewhat outdated and inconsistent with the updated model:

suggestion role

...
Authors MUST ensure that a suggestion contains either one insertion child or one deletion child or ensure that it contains two children where one is an insertion and the other is a deletion. Authors MUST ensure a suggestion does not contain any other children.
...

In particular:

• it refers to "children" rather than "accessibility children". This seems to unnecessarily restrict valid accessibility tree structures such as "generic/role none" intervening. For example, it would appear to prevent patterns such as:

  <p>
    The best pet is a
    <span role="suggestion">
      <div>
        <span role="deletion">cat</span>
        <span role="insertion">dog</span>
      </div>
    </span>
  </p>
  

• it uses "contains"; my assumption is that this is intended to mean "contains in the descendant accessibility tree", rather than being strictly limited to DOM-wrapped children. This interpretation would already account for cases involving aria-owns and generic intervening elements, provided that the notion of "accessibility children" is applied consistently.
• it must not be empty. I assume this is intentional, although it is not consistent with other patterns for "allowed accessibility child roles" such as menu, menubar, tree, treegrid, ...

[pkra]

it refers to "children" rather than "accessibility children"

From a quick look, there are more roles definitions that use "child".

it must not be empty.

This would not be editorial.

I would suggest to split this into two separate issues.

[giacomo-petri]

Sure, I can do that. I'm just wondering if we want to allow it to be empty first. If so I can create a separate issue/PR for that.