There are separate filters for IDs, classes, attribute local names, and
element state.
Also, we invalidate siblings of elements matched against the selector
list of :nth-child(... of <selector list>) by marking matched elements
with NODE_HAS_SLOW_SELECTOR_NTH_OF.
The only remaining invalidation case invalidation case is
`:nth-child(An+B of :has())` (bug 1818155), which should not block
shipping `layout.css.nth-child-of.enabled`, because :has(...) is still
being implemented (bug 418039).
Depends on D172352
Differential Revision: https://phabricator.services.mozilla.com/D171936
This implements the easy / straight-forward parts of the :where / :is
selectors.
The biggest missing piece is to handle properly invalidation when there
are combinators present inside the :where. That's the hard part of this,
actually.
But this is probably worth landing in the interim. This fixes some of
the visitors that were easy to fix.
Differential Revision: https://phabricator.services.mozilla.com/D70788
This improves cache locality and reduces allocations during parsing.
Note that this reverses the iteration order within a sequence of simple selectors,
but that shouldn't matter.
Also, simplify all the pre-snapshot attribute hacks in the script and style
code.
MozReview-Commit-ID: 6c9ipeb7Tnr
Signed-off-by: Emilio Cobos Álvarez <emilio@crisal.io>