For duplicate style sheets with identical content, `StylesheetContents`
can be reused to avoid redundant parsing of the inline style sheets.
Since duplicate stylesheets is a common case with web components, this
change will significantly improve performance. Additionally, the cache
hit rate of stylo's `CascadeDataCache` can now be significantly
improved.
When shared `StylesheetContents` is modified, copy-on-write will occur
to avoid affecting other sharers. And then updates the references to
`CssRule` or `PropertyDeclarationBlock` stored in the CSSOMs to ensure
that modifications are made only on the new copy.
Signed-off-by: sharpshooter_pt <ibluegalaxy_taoj@163.com>
Note that `StyleRule` may not have the `CssRules` readily available,
they may need to be created. So the previous approach of providing
`CSSGroupingRule` with the `CssRules` is no good: it would require
writing them in advance, just in case they end up being used.
Therefore, this removes the `CSSGroupingRule::rules` field. Instead,
they are lazily obtained in `CSSGroupingRule::rulelist()` by downcasting
and calling the appropriate method for the subclass.
Testing: covered by WPT
Fixes: #36245
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
Fixes warnings from rust-lang/rust#44229 when `--enable-commonmark` is
passed to rustdoc.
This is mostly a global find-and-replace for bare URIs on lines by
themselves in doc comments.
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).