Activity Log: register wp-build polyfills so the admin bundle loads

[dhasilva]

Fixes #

Proposed changes

• The Activity Log admin bundle depends on the wp-theme script handle (introduced when @wordpress/ui was bumped 0.13 → 0.17 here, which now depends on @wordpress/theme). WordPress core does not register that handle, so WP_Scripts::do_items() silently dropped the entire bundle and the page rendered as an empty root node — no console error.
• Register the wp-build polyfills on the Activity Log screen via WP_Build_Polyfills::register(), mirroring the pattern already used by Forms, Backup, and My Jetpack. The call runs in admin_init() (hooked to load-{page_suffix}), so it stays page-scoped and never touches other admin requests.
• Added automattic/jetpack-wp-build-polyfills to the activity-log package's composer.json.

Note: this only affects trunk. The @wordpress/ui 0.17 bump is not part of the jetpack/branch-16.0.1 release (which still pins 0.13), so shipped Activity Log builds are unaffected.

Related product discussion/links

Does this pull request change what data or activity we track or use?

No.

Testing instructions

• On a site running WordPress without Gutenberg active (e.g. WP 6.9.x), connect Jetpack as a user and ensure the Activity Log menu item is available.
• Navigate to Jetpack → Activity Log (wp-admin/admin.php?page=jetpack-activity-log).
• Confirm the page renders the full Activity Log UI — the searchable DataViews timeline with events, filters, and pagination — rather than a blank content area.
• Optionally, view source / inspect the network panel and confirm both the activity-log build/index.js bundle and the wp-theme polyfill script are loaded.

[github-actions]

Are you an Automattician? Please test your changes on all WordPress.com environments to help mitigate accidental explosions.

• To test on WoA, go to the Plugins menu on a WoA dev site. Click on the "Upload" button and follow the upgrade flow to be able to upload, install, and activate the Jetpack Beta plugin. Once the plugin is active, go to Jetpack > Jetpack Beta, select your plugin (Jetpack), and enable the fix/activity-log-blank branch.
• To test on Simple, run the following command on your sandbox:

bin/jetpack-downloader test jetpack fix/activity-log-blank

Interested in more tips and information?

• In your local development environment, use the jetpack rsync command to sync your changes to a WoA dev blog.
• Read more about our development workflow here: PCYsg-eg0-p2
• Figure out when your changes will be shipped to customers here: PCYsg-eg5-p2

[github-actions]

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Code Coverage Summary

Coverage changed in 1 file.

File	Coverage	Δ%	Δ Uncovered
projects/packages/activity-log/src/class-jetpack-activity-log.php	0/53 (0.00%)	0.00%	7 💔

Full summary · PHP report · JS report

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