UI: Fix panel layout resizing do not apply when done too fast

[jorge-ji]

Closes #25759

What I did

Fixed resizing of panel not applying when done too fast.
The fix was done by changing a comparison condition in "useLayoutEffect()". Instead of using a variable ("prevManagerLayoutStateRef") that was also modified by another function ("useEffect()") that could execute at the same time, it now uses a variable that is only modified by the own function, ensuring that the supposed layout values are not changed after they are set.

panel_resizing.mp4

Checklist for Contributors

Testing

The changes in this PR are covered in the following automated tests:

• stories
• unit tests
• integration tests
• end-to-end tests

Manual testing

This section is mandatory for all contributions. If you believe no manual test is necessary, please state so explicitly. Thanks!

1. Run the default sandbox yarn start
2. Try to resize any panel quickly

Documentation

• Add or update documentation reflecting your changes
• If you are deprecating/removing a feature, make sure to update
  MIGRATION.MD

Checklist for Maintainers

• When this PR is ready for testing, make sure to add ci:normal, ci:merged or ci:daily GH label to it to run a specific set of sandboxes. The particular set of sandboxes can be found in code/lib/cli/src/sandbox-templates.ts

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  Available labels

  • bug: Internal changes that fixes incorrect behavior.
  • maintenance: User-facing maintenance tasks.
  • dependencies: Upgrading (sometimes downgrading) dependencies.
  • build: Internal-facing build tooling & test updates. Will not show up in release changelog.
  • cleanup: Minor cleanup style change. Will not show up in release changelog.
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  • feature request: Introducing a new feature.
  • BREAKING CHANGE: Changes that break compatibility in some way with current major version.
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[jorge-ji]

@ndelangen , hello, sorry to bother, but I'm a bit confused with what the check errors mean.

[JReinhold]

I can't really reproduce the original issue with or without this patch, but I trust that this fixes it. At least I can confirm that it doesn't break anything based on my testing.

Thanks. ❤️

[JReinhold]

Maybe I was wrong, it appears that this breaks the keyboard shortcuts for toggling the sidebar/addon panel/fullscreen, as is also evident by the failing e2e tests.

It's not about the keyboard though, using the menu dropdown to toggle doesn't work either.

I think it's because of the added state to the dependency array.
If you toggle the layout via keyboard it will update the manager layout state. This will now trigger this useLayoutEffect, which will immediately set the manager layout state back to what it was initially.

[jorge-ji]

Sorry for the delay, I believe that fixes the broken toggles, all e2e tests are also passing. I'm not sure why test-portable-stories-svelte is failing, hopefully it's not due to the changes.