Implement a URL-generic type for ListStyleImage
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This should fix the following two "expected to fail" tests described in https://github.com/servo/servo/issues/18015:
- getComputedStyle(elem) for url() listStyleImage uses the resolved URL
and elem.style uses the original URL
- getComputedStyle(elem) for url() listStyle uses the resolved URL
and elem.style uses the original URL
I updated the test failure expectations by removing the corresponding `.ini` file.
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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#18015 (github issue number if applicable).
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- [x] There are tests for these changes OR
- [ ] These changes do not require tests because _____
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This should fix the following two "expected to fail" tests:
- getComputedStyle(elem) for url() listStyleImage uses the resolved URL
and elem.style uses the original URL
- getComputedStyle(elem) for url() listStyle uses the resolved URL
and elem.style uses the original URL
fix test-tidy errors
fix style unit test
use the Parse trait instead of ParseWithContext
fix stylo test and geckolib build
move all specified url parse code to parse trait and remove refs to unused type
I've deliberately tried to keep things similarly structured as in the longhand files. I.e. if a given property is in e.g. longhand/box.mako.rs, the shorthand stuff that relates to the same property is in shorthand/box.mako.rs and so forth.
