When naming from content, determine whether owned and contained content are treated differently by the accessible name calculation

[mcking65]

Is content that is owned via aria-owns ignored by the name calculation when an element is named by its content?

If so, this will require modification of the labeling guidance for treeitems and menuitems in the tree and menu patterns.

[jnurthen]

Implementations differ on this.

FF (tested 48ESR & 54 -Dev Edition). FF ignores aria-owns when computing the accessible name
Chrome (Tested Canary). Chrome Canary uses aria-owns when computing the accessible name and will include it along with any natural decendents

IMO Chrome's behaviour is a bug and it breaks code such as http://oaa-accessibility.org/example/42/ which uses aria-owns within the tree.

[jnurthen]

Logged bug against Chrome - https://bugs.chromium.org/p/chromium/issues/detail?id=702811

[jnurthen]

ARIA issue w3c/aria#538

[jnurthen]

So it seems FF is moving to the Chrome model. I don't believe there is anything to do here - but @mcking65 please confirm