2077441 - Add ShellService.isDefaultBrowserAsync compatibility wrapper to Beta and Release for Newtab trainhop

Status: ASSIGNED

(Firefox :: Shell Integration, task)

Description

[Jan Varga [:janv]]

Bug 2074009 is introducing ShellService.isDefaultBrowserAsync() and migrating callers, including ASRouter targeting, to the new API.

Newtab trainhop CI runs ASRouter targeting tests against the latest Beta and Release builds, where the new async method is not yet available. This causes failures such as:

TEST-UNEXPECTED-FAIL | browser/components/asrouter/tests/browser/browser_asrouter_newtab_messages.js | test_states_targeting_recompose - Uncaught exception in test - TypeError: Cannot stub non-existent own property isDefaultBrowserAsync

An example of an affected job:
Linux 24.04 opt Mochitest-browser for Newtab using latest Release builds

Add a minimal compatibility wrapper that returns a Promise and forwards to the existing synchronous isDefaultBrowser(). The real implementation has already landed on main and will replace this wrapper through the normal release cycle.

Ideally, the wrapper should be uplifted to both Beta and Release before the ASRouter targeting migration in D330323 lands. I understand that the affected trainhop jobs are tier 2 and their failures do not require backouts, so this is not a strict landing requirement. Still, uplifting first would keep these jobs passing instead of leaving them failing for several days/weeks.

Comment 1

[Jan Varga [:janv]]

Attachment: Bug 2077441 - Add ShellService.isDefaultBrowserAsync compatibility wrapper on Beta for Newtab trainhop; r=#firefox-desktop-core-reviewers,#gtk-reviewers

Add a Promise-returning wrapper around the existing synchronous check on Beta
so the next Release provides the async API required by Newtab trainhop CI.

This keeps the affected tests passing until the real implementation from bug
2074009 reaches Release through the normal release cycle.