<!-- Please describe your changes on the following line: -->
This PR speculatively calls paint worklets during style, which increases the concurrency, since it increases the chance that the cache will have the right result in it when it comes to layout. The speculation is wasted effort if the size of the element has changed, but this is often not the case.
---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#17486 and #17369.
- [X] These changes do not require tests because it's a performance improvement
<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->
<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->
Source-Repo: https://github.com/servo/servo
Source-Revision: cf5602e84f17d14b6a9abb77f1de6460db070921
126613911f