Auto merge of #18790 - upsuper:scope, r=emilio

Support :scope pseudo-class

This fixes [bug 1406817](https://bugzilla.mozilla.org/show_bug.cgi?id=1406817).

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tests/wpt/metadata/MANIFEST.json

@@ -152045,6 +152045,18 @@
      {}
     ]
    ],
+   "css/selectors4/scope-without-scoping.html": [
+    [
+     "/css/selectors4/scope-without-scoping.html",
+     [
+      [
+       "/css/reference/ref-filled-green-100px-square.xht",
+       "=="
+      ]
+     ],
+     {}
+    ]
+   ],
    "css/selectors4/selector-required.html": [
     [
      "/css/selectors4/selector-required.html",
@@ -538672,6 +538684,10 @@
    "607553f41a33ce3630752cdf027c9f904833a19d",
    "reftest"
   ],
+  "css/selectors4/scope-without-scoping.html": [
+   "f70b8d60543c5a28fcf955b1780f15c03d60991a",
+   "reftest"
+  ],
   "css/selectors4/selector-required-ref.html": [
    "815bc765614b4c2e3d8f8f6303e6bb2ee0989c23",
    "support"
@@ -570101,7 +570117,7 @@
    "testharness"
   ],
   "dom/nodes/Element-closest.html": [
-   "4171fb8b70948ba2617e05b118aaf5d9367e916f",
+   "5abddb81959019267d8b69002ee95b011b2fe34a",
    "testharness"
   ],
   "dom/nodes/Element-firstElementChild-entity-xhtml.xhtml": [

tests/wpt/metadata/dom/nodes/Element-closest.html.ini

@@ -4,3 +4,6 @@
     bug: https://github.com/servo/servo/issues/10781
     expected: FAIL
 
+  [Element.closest with context node 'test4' and selector ':has(> :scope)']
+    expected: FAIL
+