2021889 - Make nsContentPermissionHelper aware of platform permission when appropriate

Status: NEW

(Core :: DOM: Core & HTML, enhancement)

Description

[Kagami Rosylight 🏳️‍🌈🏳️‍⚧️ [:saschanaz] (they/them)]

Currently ContentPermissionRequestBase calls nsContentPermissionUtils::AskPermission which calls back if the browser allows the permission, which is called by permission UI.

But we have OS permission nowadays in 2026 even on desktop platforms, meaning we should also consider them. For web content it doesn't matter whether it's the browser or the OS denying the permission, so ideally ContentPermissionHelper should only call the Allow callback when both are allowed, and call Cancel when any one of them are denied.

We have some custom logic in dom/geolocation which should be moved to the helper.