style: sync changes from mozilla-central
See each individual commit for details. This also cherry-picks #23463 with a few fixes that were needed in Gecko-only code.
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Remove unused code (3/N)
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Third PR in a series of PRs to remove unused/dead code from servo, powered by an (upcoming) tool of mine. Please take a look and tell me if you want to keep something.
* First PR: #23477
* Second PR: #23498
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- [ ] These changes fix #___ (GitHub issue number if applicable)
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No longer needed now that the case-sensitive flag for attributes selectors is
supported.
Update user-agent CSS sheet to use the standard flag.
Fixes#23227
The following IDLs have the src/href attributes typed as a DOMString
while in the spec the attribute has been updated to be a USVString:
- HTMLIFrameElement
- HTMLImageElement
- HTMLInputElement
- HTMLLinkElement
- HTMLMediaElement
- HTMLScriptElement
