Auto merge of #9067 - nox:unenumerable-named-properties, r=jdm

Make NamedNodeMap's named properties unenumerable

https://dom.spec.whatwg.org/#dom-htmlcollection-item

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tests/wpt/metadata/dom/nodes/Document-getElementsByTagName.html.ini

@@ -3,6 +3,3 @@
   [Shouldn't be able to set unsigned properties on a HTMLCollection (strict mode)]
     expected: FAIL
 
-  [hasOwnProperty, getOwnPropertyDescriptor, getOwnPropertyNames]
-    expected: FAIL
-

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

@@ -1,5 +0,0 @@
-[Element-children.html]
-  type: testharness
-  [HTMLCollection edge cases 1]
-    expected: FAIL
-

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

@@ -3,6 +3,3 @@
   [Shouldn't be able to set unsigned properties on a HTMLCollection (strict mode)]
     expected: FAIL
 
-  [hasOwnProperty, getOwnPropertyDescriptor, getOwnPropertyNames]
-    expected: FAIL
-

tests/wpt/metadata/dom/nodes/attributes.html.ini

@@ -6,18 +6,6 @@
   [getAttributeNames tests]
     expected: FAIL
 
-  [Own property correctness with basic attributes]
-    expected: FAIL
-
-  [Own property correctness with non-namespaced attribute before same-name namespaced one]
-    expected: FAIL
-
-  [Own property correctness with namespaced attribute before same-name non-namespaced one]
-    expected: FAIL
-
-  [Own property correctness with two namespaced attributes with the same name-with-prefix]
-    expected: FAIL
-
   [Own property names should only include all-lowercase qualified names for an HTML element in an HTML document]
     expected: FAIL
 

tests/wpt/metadata/html/dom/documents/dom-tree-accessors/document.forms.html.ini

@@ -1,5 +0,0 @@
-[document.forms.html]
-  type: testharness
-  [document.forms iteration]
-    expected: FAIL
-