Auto merge of #25223 - pshaughn:xmlerrortype, r=Manishearth

Changed error type on qname, per spec

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As specified in https://dom.spec.whatwg.org/#validate invalid QNames when creating a namespaced document/element/attribute get an invalid character exception, not a namespace exception.

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- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #25110

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- [X] There are tests for these changes

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components/script/dom/bindings/xmlname.rs

@@ -10,15 +10,10 @@ use html5ever::{LocalName, Namespace, Prefix};
 
 /// Validate a qualified name. See https://dom.spec.whatwg.org/#validate for details.
 pub fn validate_qualified_name(qualified_name: &str) -> ErrorResult {
+    // Step 2.
     match xml_name_type(qualified_name) {
-        XMLName::InvalidXMLName => {
-            // Step 1.
-            Err(Error::InvalidCharacter)
-        },
-        XMLName::Name => {
-            // Step 2.
-            Err(Error::Namespace)
-        },
+        XMLName::InvalidXMLName => Err(Error::InvalidCharacter),
+        XMLName::Name => Err(Error::InvalidCharacter), // see whatwg/dom#671
         XMLName::QName => Ok(()),
     }
 }