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When we resolve style for an eagerly computed pseudo-element, such as an anonymous box, if there are no matching rules we currently just clone the parent's style. We should only do that if `inherit_all` is true, otherwise we should inherit only the inherited properties from the parent.
I was going to use `.unwrap_or_default()` on the result of looking up `precomputed_pseudo_element_decls`, but that didn't seem to work since that map lookup returns a reference and not a `Vec` itself.
r? @emilio
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- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix https://bugzilla.mozilla.org/show_bug.cgi?id=1329121
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Source-Repo: https://github.com/servo/servo
Source-Revision: ebd4a8b3ee1aab910ef714420a814912fec31e30
84d8fd3b17