Bug 286928 – AX: move definition of Mac NSAccessibility constants to a common header file, remove guards

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

[Dominic Mazzoni]

To make it easier to identify and audit all of the accessibility constants in WebKit, move the definition of NSAccessibility constants to a common header file and remove guards.

We currently have definitions like this in a few different files:

#ifndef NSAccessibilityCurrentStateChangedNotification
#define NSAccessibilityCurrentStateChangedNotification @"AXCurrentStateChanged"
#endif

The #ifndef guard is misleading because it implies that it's preventing us from redefining a constant defined in a system header. But in fact, most system-defined accessibility constants are symbols, so the #ifndef isn't doing anything, and we were in fact redefining some symbol names before being deleted in a previous change.

As a follow-up I think we should consider switching to symbols for these constants in WebKit because then we'd get a linker error if we duplicate a system symbol.

[Radar WebKit Bug Importer]

<rdar://problem/144089453>

[Dominic Mazzoni]

Pull request: https://github.com/WebKit/WebKit/pull/39915

[EWS]

Committed 289842@main (9644e79bbfa1): <https://commits.webkit.org/289842@main>

Reviewed commits have been landed. Closing PR #39915 and removing active labels.