Update referrer computation
The PR updates the request's referrer computation in consideration with the recent changes in [w3c/webappsec-referrer-policy#135](https://github.com/w3c/webappsec-referrer-policy/pull/135).
---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#27030 and fix#14505
- [x] There are tests for these changes
Implement MediaStreamAudioDestinationNode, MediaStreamAudioSourceNode, MediaStreamTrackAudioSourceNode
Progress in https://github.com/servo/servo/issues/26097
This is a draft since we need the data channels stuff to land first
(also I need to make sure we're passing WPT)
Implement HTMLFormElement.requestSubmit()
<!-- Please describe your changes on the following line: -->
This PR contains an implementation of [HTMLFormElement.requestSubmit()](https://html.spec.whatwg.org/multipage/forms.html#dom-form-requestsubmit)
This is literally my first hundred lines of Rust code, so if I crossed a few sacred lines here and there, please go easy on me :)
---
<!-- 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#23417
<!-- Either: -->
- [x] [WPT tests](https://github.com/servo/servo/blob/master/tests/wpt/web-platform-tests/html/semantics/forms/the-form-element/form-requestsubmit.html) for these changes
There are two tests that still fail because we don't support `:invalid` CSS selector (see #10781). I verified that they pass if you change them to not use `:invalid`. Should be unlocked by #26729.
<!-- 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. -->
animations: Finish support for fractional iteration counts
This change also improves support for creating animations with negative
delays, as that is necessary to test support for fractional iteration
lengths.
Fixes: #14858
<!-- Please describe your changes on the following line: -->
---
<!-- 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#14858
- [x] There are tests for these changes
<!-- 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. -->
This change also improves support for creating animations with negative
delays, as that is necessary to test support for fractional iteration
lengths.
This change also adjusts existing Servo animation tests which assumed
that advancing to the exact moment of the end of the animation would be
considered "before the end." With this change, this moment is "after the
end."
Fixes: #14858
Fix nested modules while imported under more than 3 levels
This is kind of workaround to fix the issue but #26903 should provide much better solution to remove the checking.
---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#27029
- [x] There are tests for these changes
<!-- 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. -->
Cancel animations for nodes which are removed from the DOM
This includes nodes which are being reparented.
---
<!-- 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] There are tests for these changes
<!-- 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. -->
Silently ignore failures to queue websocket tasks
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#26977
- [x] There are tests for these changes
Upgrade flake8/pyflakes for Py3 compatibility
<!-- Please describe your changes on the following line: -->
---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `___` with appropriate data: -->
- [ ] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #___ (GitHub issue number if applicable)
<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because ___
<!-- 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. -->
