Auto merge of #16841 - bzbarsky:fix-moz-any-matching, r=emilio

Fix the situation when :any-link starts or stops matching to actually restyle correctly.

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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=1364335

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components/style/gecko/non_ts_pseudo_class_list.rs

@@ -38,7 +38,9 @@
  * possible.
  *
  * $gecko_type can be either "_" or an ident in Gecko's CSSPseudoClassType.
- * $state can be either "_" or an expression of type ElementState.
+ * $state can be either "_" or an expression of type ElementState.  If present,
+ *        the semantics are that the pseudo-class matches if any of the bits in
+ *        $state are set on the element.
  * $flags can be either "_" or an expression of type NonTSPseudoClassFlag,
  * see selector_parser.rs for more details.
  */

components/style/restyle_hints.rs

@@ -343,7 +343,7 @@ impl<'a, E> Element for ElementWrapper<'a, E>
                                                           &mut |_, _| {})
         }
         match self.snapshot().and_then(|s| s.state()) {
-            Some(snapshot_state) => snapshot_state.contains(flag),
+            Some(snapshot_state) => snapshot_state.intersects(flag),
             None => {
                 self.element.match_non_ts_pseudo_class(pseudo_class,
                                                        relations,