Add support for transition{run,start,cancel} events

[someonewithpc]

Closes #26065

Summary

Add support for transitionstart, transitionrun and transitioncancel events, avoiding using the useEffect hacky workaround

How did you test this change?

yarn test packages/react-dom/src/__tests__/ReactDOMEventPropagation-test.js

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[react-sizebot]

Comparing: 14f50ad...bd5ecea

Critical size changes

Includes critical production bundles, as well as any change greater than 2%:

Name	+/-	Base	Current	+/- gzip	Base gzip	Current gzip
oss-stable/react-dom/cjs/react-dom.production.min.js	+0.18%	169.11 kB	169.41 kB	+0.12%	52.76 kB	52.82 kB
oss-experimental/react-dom/cjs/react-dom.production.min.js	+0.18%	170.91 kB	171.22 kB	+0.15%	53.27 kB	53.35 kB
facebook-www/ReactDOM-prod.classic.js	+0.10%	590.58 kB	591.16 kB	+0.08%	103.86 kB	103.94 kB
facebook-www/ReactDOM-prod.modern.js	+0.10%	566.68 kB	567.26 kB	+0.10%	100.01 kB	100.11 kB
test_utils/ReactAllWarnings.js	Deleted	64.04 kB	0.00 kB	Deleted	16.02 kB	0.00 kB

Significant size changes

Includes any change greater than 0.2%:

Expand to show

Name	+/-	Base	Current	+/- gzip	Base gzip	Current gzip
test_utils/ReactAllWarnings.js	Deleted	64.04 kB	0.00 kB	Deleted	16.02 kB	0.00 kB

Generated by 🚫 dangerJS against bd5ecea

[github-actions]

This pull request has been automatically marked as stale. If this pull request is still relevant, please leave any comment (for example, "bump"), and we'll keep it open. We are sorry that we haven't been able to prioritize reviewing it yet. Your contribution is very much appreciated.

[eps1lon]

Would love to get this into 19. Can you rebase to resolve merge conflicts?

[someonewithpc]

Would love to get this into 19. Can you rebase to resolve merge conflicts?

I see you went ahead and did the rebase :) Do you need me to do anything?

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[eps1lon]

I see you went ahead and did the rebase :) Do you need me to do anything?

I wasn't sure if we lost you. We're currently working on React 19 and I wanted to make sure this is included.

Sorry for the delay but this is good to go now 👍🏻

Works: https://codesandbox.io/p/sandbox/react-transition-events-lk98y8?file=%2Fsrc%2Findex.js%3A6%2C83

I'll just adjust the tests since these events are not actually cancelable.

[someonewithpc]

I wasn't sure if we lost you

Fair assumption, but I was just planning to get around to this basically now, after work. Given it got marked stale I thought it would just sit here. Thanks for the update, and I'm looking forward to using this

[eps1lon]

Doesn't really matter since synthetic events don't need to match real events. But better to test them closer to what they'll look when dispatched from user agents.

[eps1lon]

@someonewithpc Thank you!