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We currently have a type `ScriptChan` in the constellation, which is named after its implementation rather than its semantics. In the spec, the nearest concept seems to be event loop https://html.spec.whatwg.org/multipage/#event-loop.
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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 do not require tests because renaming.
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Source-Repo: https://github.com/servo/servo
Source-Revision: 91a2e7614ce1679a44a3c390a1fc792bf381f271
