script: Add message to HierarchyRequestError (#40366)

Adds an optional error message to HierarchyRequestError

Testing: refactor
Fixes: one item in #39053

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Signed-off-by: Austin Willis <austinwillis8@gmail.com>

components/script/dom/css/cssrulelist.rs

@@ -38,7 +38,7 @@ impl Convert<Error> for RulesMutateError {
         match self {
             RulesMutateError::Syntax => Error::Syntax(None),
             RulesMutateError::IndexSize => Error::IndexSize(None),
-            RulesMutateError::HierarchyRequest => Error::HierarchyRequest,
+            RulesMutateError::HierarchyRequest => Error::HierarchyRequest(None),
             RulesMutateError::InvalidState => Error::InvalidState(None),
         }
     }