in effect, implement plumbing for pseudo attribute from: http://dev.w3.org/2006/xbl2/Overview.html#the-pseudo-attribute
See https://bugs.webkit.org/show_bug.cgi?id=50790#c3 for specific steps on how to do this.
Created attachment 78063 [details] WIP: Almost ready
(In reply to comment #2) > Created an attachment (id=78063) [details] > WIP: Almost ready I am not sure I need both CSSSelector::PseudoShadowElement and CSSSelector::ShadowHost, but it does make the logic easier to understand. WDYT?
Still to do: 1) We're supposed to throw SYNTAX_ERR on unknown pseudo elements. How are we going to handle this now? 2) Unscrew-up pseudo element selector serialization.
Created attachment 78126 [details] WIP: Serialization almost works.
Created attachment 78262 [details] Ready for review
Created attachment 78274 [details] Corrected the issue with multiple specifiers.
Comment on attachment 78274 [details] Corrected the issue with multiple specifiers. I wrote a comprehensive test for selectors to double-check that I didn't screw anything up, and it turns out I did! :) New patch coming up.
Created attachment 78338 [details] Patch
(In reply to comment #9) > Created an attachment (id=78338) [details] > Patch Now with tests! I can't believe we didn't good have coverage for namespaces/elements/specifier_lists combinations.
Comment on attachment 78338 [details] Patch r=me. Looks good.
Committed r75543: <http://trac.webkit.org/changeset/75543>