Auto merge of #19743 - EdgarChen:unresolved, r=heycam

style: Remove :unsolved pseudo-class

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This is the servo part changes of https://bugzilla.mozilla.org/show_bug.cgi?id=1417829.

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix https://bugzilla.mozilla.org/show_bug.cgi?id=1417829.

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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because this PR is to remove a feature.

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components/style/element_state.rs

@@ -71,8 +71,7 @@ bitflags! {
         const IN_OPTIONAL_STATE = 1 << 22;
         /// <https://html.spec.whatwg.org/multipage/#selector-read-write>
         const IN_READ_WRITE_STATE = 1 << 22;
-        /// Non-standard: Older custom-elements spec.
-        const IN_UNRESOLVED_STATE = 1 << 23;
+        /// There is a free bit at 23.
         /// <https://html.spec.whatwg.org/multipage/#selector-visited>
         const IN_VISITED_STATE = 1 << 24;
         /// <https://html.spec.whatwg.org/multipage/#selector-link>

components/style/gecko/non_ts_pseudo_class_list.rs

@@ -43,7 +43,6 @@ macro_rules! apply_non_ts_list {
     ($apply_macro:ident) => {
         $apply_macro! {
             bare: [
-                ("unresolved", Unresolved, unresolved, IN_UNRESOLVED_STATE, _),
                 ("-moz-table-border-nonzero", MozTableBorderNonzero, mozTableBorderNonzero, _, PSEUDO_CLASS_ENABLED_IN_UA_SHEETS),
                 ("-moz-browser-frame", MozBrowserFrame, mozBrowserFrame, _, PSEUDO_CLASS_ENABLED_IN_UA_SHEETS_AND_CHROME),
                 ("link", Link, link, IN_UNVISITED_STATE, _),

components/style/gecko/wrapper.rs

@@ -2029,7 +2029,6 @@ impl<'le> ::selectors::Element for GeckoElement<'le> {
             NonTSPseudoClass::Optional |
             NonTSPseudoClass::MozReadOnly |
             NonTSPseudoClass::MozReadWrite |
-            NonTSPseudoClass::Unresolved |
             NonTSPseudoClass::FocusWithin |
             NonTSPseudoClass::MozDragOver |
             NonTSPseudoClass::MozDevtoolsHighlighted |