Bug 292844 – AX: Fix permitted values for aria-setsize, aria-posinset (both >= 1) and specify fallbacks

• Status: RESOLVED
• Resolution: FIXED
• Component: Accessibility

[Rahim Abdi]

Core-AAM will be updated to resolve inconsistencies around possible values for aria-setsize/aria-posinset. Essentially:

aria-setsize:
- Empty string is provided or the attribute is missing (undefined) = ignore or set on per-role basis
- Positive integers (i.e., whole numbers > 0) = set to specified integer
- 0, negative numbers or malformed/invalid values  = indeterminate (i.e., "-1"). In this case, also set aria-posinset = 1

aria-posinset:
- Empty string is provided or the attribute is missing (undefined) = ignore or set on per-role basis
- Positive integers (i.e., whole numbers > 0) = set to specified integer
- 0, negative numbers or malformed/invalid values  = 1

ARIA PR #2341: https://github.com/w3c/aria/pull/2341

[Radar WebKit Bug Importer]

<rdar://problem/151113693>

[Rahim Abdi]

Pull request: https://github.com/WebKit/WebKit/pull/45225

[EWS]

Committed 295814@main (4220ccde4c53): <https://commits.webkit.org/295814@main>

Reviewed commits have been landed. Closing PR #45225 and removing active labels.