Use whether we've computed any viewport unit instead.
This is more accurate (we avoid restyling unnecessarily if we've found anything
ever on the stylesheet, but that hasn't matched).
This has the benefit of also matching Gecko, and simplify some code and
fishyness around, and also hopefully speeding up stylesheet parsing.
The alias is left there temporarilly and will be removed completely in a later commit where
also components/style/gecko/generated/structs_{debug|release}.rs are re-generated (they still
use the old alias).
Allow loading multiple stylesheets for the same link element.
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#16399
- [x] There are tests for these changes
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Implemented response validation part of
https://w3c.github.io/webappsec-subresource-integrity/.
Implemented step eighteen of the main fetch. If a request has integrity
metadata, then following steps are performed
*Wait for response body
*If the response does not have a termination reason and response does not
match request’s integrity metadata, set response to a
network error.# Please enter the commit message for your changes. Lines starting
