LibWeb: Update attribute name validation in Element.toggleAttribute

This now follows the latest specification steps.

Libraries/LibWeb/DOM/Element.cpp

@@ -461,8 +461,8 @@ bool Element::has_attribute_ns(Optional<FlyString> const& namespace_, FlyString
 // https://dom.spec.whatwg.org/#dom-element-toggleattribute
 WebIDL::ExceptionOr<bool> Element::toggle_attribute(FlyString const& name, Optional<bool> force)
 {
-    // 1. If qualifiedName does not match the Name production in XML, then throw an "InvalidCharacterError" DOMException.
-    if (!Document::is_valid_name(name.to_string()))
+    // 1. If qualifiedName is not a valid attribute local name, then throw an "InvalidCharacterError" DOMException.
+    if (!is_valid_attribute_local_name(name))
         return WebIDL::InvalidCharacterError::create(realm(), "Attribute name must not be empty or contain invalid characters"_string);
 
     // 2. If this is in the HTML namespace and its node document is an HTML document, then set qualifiedName to qualifiedName in ASCII lowercase.

Tests/LibWeb/Text/expected/Element-toggleAttribute-invalid-name.txt

@@ -1,2 +1,2 @@
 PASS (''): InvalidCharacterError
-PASS ('0'): InvalidCharacterError
+PASS ('='): InvalidCharacterError

Tests/LibWeb/Text/expected/wpt-import/dom/nodes/attributes.txt

@@ -2,13 +2,13 @@ Harness status: OK
 
 Found 67 tests
 
-65 Pass
-2 Fail
+66 Pass
+1 Fail
 Pass	When qualifiedName does not match the Name production, an INVALID_CHARACTER_ERR exception is to be thrown. (toggleAttribute)
 Pass	toggleAttribute should lowercase its name argument (upper case attribute)
 Pass	toggleAttribute should lowercase its name argument (mixed case attribute)
 Pass	toggleAttribute should not throw even when qualifiedName starts with 'xmlns'
-Fail	Basic functionality should be intact. (toggleAttribute)
+Pass	Basic functionality should be intact. (toggleAttribute)
 Pass	toggleAttribute should not change the order of previously set attributes.
 Pass	toggleAttribute should set the first attribute with the given name
 Pass	toggleAttribute should set the attribute with the given qualified name

Tests/LibWeb/Text/input/Element-toggleAttribute-invalid-name.html

@@ -15,10 +15,10 @@
         }
 
         try {
-            element.toggleAttribute("0");
-            println("FAIL ('0')");
+            element.toggleAttribute("=");
+            println("FAIL ('=')");
         } catch (err) {
-            println("PASS ('0'): " + err.name);
+            println("PASS ('='): " + err.name);
         }
     });
 </script>