Update rust-mozjs
These changes adjust our uses of the rust-mozjs APIs to accommodate the changes in https://github.com/servo/rust-mozjs/pull/450.
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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#22342.
- [x] There are tests for these changes
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Don't panic when executing userscripts
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#22685
- [x] These changes do not require tests because there is no automation for testing userscripts.
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Reduce unnecessary iframe size messages
This should be an improvement on pages that include iframes, since we currently run two layout jobs for every display-oriented layout request. When building the display list, we send a message to the constellation that includes the sizes of all iframes present, and the constellation sends resize messages to the script thread. This results in a mouse event on the outer page causing all frames to be re-laid out even if no changes occurred to the iframe sizes, which is ridiculous.
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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#22394
- [x] These changes do not require tests because there is no way to test this internal detail.
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Implement HTMLMediaElement poster attribute
- [X] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#22288
- [x] There are tests for these changes
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Some janitoring over the layout crate
This PR moves a bunch of code around and makes some methods from one-use traits into inherent methods.
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Implement Element::set_url_attribute
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- [ ] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#22568
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Implement Ended media attribute
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This PR should implement:
* New method `HTMLMediaElement::earliest_possible_position()` for the [earliest possible position](https://html.spec.whatwg.org/multipage/media.html#earliest-possible-position)
* `Ended` attribute following https://html.spec.whatwg.org/multipage/media.html#ended-playback
* Queue steps for when the playback position reaches the end
This PR contains placeholders for the following issues (I can rebase changes after the corresponding PRs get merged)
- #22321 (Define the Loop attribute)
- #22293 (To identify playback direction. Either forwards or backwards)
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- [X] `./mach test-tidy` does not report any errors
- [x] These changes fix#22294.
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