Devirtualize CSS error reporting.
This removes a trait object from the path of reporting a CSS error.
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] There are tests for these changes
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This will allow tracking whether there have been only additions to the
stylesheet set, and in that case don't destroy and completely rebuild the
invalidation map.
This PR accounts for the fact that the namespace table is only needed in
`NestedRuleParser`, and only for style rules, in order to simplify the setup and
be able to fix a few bugs wrt parsing of invalid rules.
Currently, attempting to parse an at-rule that is out of place, such as
an @import rule after a regular style rule, will cause the parser state
to be set to Invalid. This will cause any following at-rule to be
rejected until we encounter a regular style rule, at which point we'll
go back to the Body state. There's nothing in the CSS specs about
needing to reject all following at-rules (or, as the comment above
Invalid says, ignoring the entire rest of the style sheet).
This causes a warning it today’s Nightly:
https://github.com/rust-lang/rust/issues/42868
… which makes the build fail because we use `#![deny(warnings)]`.
This warning is planned to become a hard error in a future Rust version.
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).
This file has become quite bloated lately. This commit deletes that file in
favor of a set of submodules.
The only noticeable change apart from code move, is converting deep_clone_foo
methods into a trait.
It also unifies logic related to different style rules in the same place.
There's some missing work, specially related to font-face and counter-style, but
I think this is worth landing in the meantime.
