Fix DuckDuckGo HTML search
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#22090
- [x] There are tests for these changes
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Implement rejectionhandled event
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#22006 .
- [x] There are more tests `PASS`ed for these changes
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Assign a name to iframes when loading the initial about:blank
Before, it would assign the name too late, causing scripts (which will not wait for another tick) to accidentally spawn pop-up windows instead of loading into the iframe.
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#21886
- [x] There are tests for these changes
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Implement unhandledrejection event
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#15412
- [x] There are tests for these changes
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Before, it would assign the name too late,
causing scripts (which will not wait for another tick)
to accidentally spawn pop-up windows instead of loading
into the iframe.
Make layout use available image data before querying the image cache.
These changes make layout more efficient for any page which contains images that have already loaded, since it does not require synchronously querying the image cache thread for each image present. It also makes reloading a page actually display the images that are already in the image cache.
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#21919
- [x] There are tests for these changes
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This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/21931)
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