Auto merge of #18092 - cbrewster:ce_domtokenlist, r=jdm

Only run DOMTokenList update steps if token was found

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components/script/dom/domtokenlist.rs

@@ -158,9 +158,9 @@ impl DOMTokenListMethods for DOMTokenList {
             } else {
                 atoms.remove(pos);
             }
+            // Step 5.
+            self.element.set_atomic_tokenlist_attribute(&self.local_name, atoms);
         }
-        // Step 5.
-        self.element.set_atomic_tokenlist_attribute(&self.local_name, atoms);
         Ok(())
     }
 

tests/wpt/metadata/custom-elements/reactions/DOMTokenList.html.ini

@@ -1,5 +0,0 @@
-[DOMTokenList.html]
-  type: testharness
-  [replace on DOMTokenList must not enqueue an attributeChanged reaction when the token to replace does not exist in the attribute]
-    expected: FAIL
-