Add support for event information in React scheduler tracks in React Native

[everettbu]

Mirror of facebook/react#35947
Original author: rubennorte

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Summary

This defines the same fiber configuration for RN as used in DOM, so we can expose event timing information in the React scheduler tracks in performance traces.

This was unblocked by #35913 and #35912.

How did you test this change?

Manually compiled the renderer and tested e2e in FB infra:

[greptile-apps]

Greptile Summary

This PR enables event timing information in React scheduler performance tracks for React Native (Fabric renderer), bringing it to parity with the DOM renderer.

• Implements trackSchedulerEvent(), resolveEventType(), and resolveEventTimeStamp() in ReactFiberConfigFabric.js to read from global.event (the RN equivalent of window.event in DOM)
• Adds a getEventType() helper with a legacy fallback that extracts event types from dispatchConfig.phasedRegistrationNames for older RN event objects that don't set the type property
• The non-Fabric renderer (ReactFiberConfigNative.js) is not updated and still uses no-op stubs — this is intentional as the feature targets Fabric only

Confidence Score: 4/5

• This PR is safe to merge — it mirrors an established DOM pattern with appropriate RN-specific adaptations and includes a well-structured legacy fallback.
• Score of 4 reflects that the change closely follows the existing DOM implementation pattern, correctly adapts it for React Native (using global.event instead of window.event), and the legacy fallback handles the RN-specific dispatchConfig event format properly. Minor deduction because the legacy fallback path introduces RN-specific complexity that could benefit from more explicit test coverage.
• No files require special attention.

Important Files Changed

Filename	Overview
packages/react-native-renderer/src/ReactFiberConfigFabric.js	Implements event tracking for React scheduler tracks in RN Fabric, mirroring the DOM config pattern with global.event instead of window.event and adding a legacy fallback via dispatchConfig.phasedRegistrationNames for older RN event objects.

_{Last reviewed commit: 627fa8f}

[greptile-apps]

_{1 file reviewed, no comments}

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[everettbu]

Upstream PR was closed or merged. Code is synced via branch mirror.