feat(addInitScript): allow passing functions as init script arguments

[pavelfeldman]

Summary

• page.addInitScript() and browserContext.addInitScript() now accept functions inside arg when called with the new { exposeFunctions: true } option, following feat(evaluate): allow passing functions as evaluate arguments #41801.
• Functions are backed by noGlobal bindings that are re-installed in every new document, so unlike evaluate(), they survive navigations.
• Disposing the returned disposable removes both the init script and the bindings backing the functions.

[github-actions]

Test results for "MCP"

7792 passed, 1269 skipped

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Merge workflow run.

[github-actions]

Test results for "tests 1"

Warning

The triggering workflow run ended with status cancelled. Results below may be incomplete — blob reports from cancelled or timed-out shards are missing, so passing/failing counts do not reflect the full test suite.

5 flaky

⚠️ [chromium-library] › library/chromium/chromium.spec.ts:299 › should report intercepted service worker requests in HAR `@chromium-ubuntu-22.04-arm-node20`
⚠️ [chromium-library] › library/chromium/chromium.spec.ts:371 › should produce network events, routing, and annotations for Service Worker `@chromium-ubuntu-22.04-arm-node20`
⚠️ [chromium-library] › library/video.spec.ts:736 › screencast › should work with video+trace `@chromium-ubuntu-22.04-arm-node20`
⚠️ [chromium-library] › library/video.spec.ts:664 › screencast › should capture full viewport `@chromium-ubuntu-22.04-node24`
⚠️ [firefox-page] › page/page-emulate-media.spec.ts:144 › should keep reduced motion and color emulation after reload `@firefox-ubuntu-22.04-node20`

50106 passed, 1190 skipped

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Merge workflow run.