LibJS: Convert supported_locales() to ThrowCompletionOr

Author: https://github.com/IdanHo
Commit: d0e5fc4576
Pull-request: https://github.com/SerenityOS/serenity/pull/10121
Reviewed-by: https://github.com/linusg ✅

Userland/Libraries/LibJS/Runtime/Intl/DisplayNamesConstructor.cpp

@@ -131,7 +131,7 @@ JS_DEFINE_NATIVE_FUNCTION(DisplayNamesConstructor::supported_locales_of)
         return {};
 
     // 3. Return ? SupportedLocales(availableLocales, requestedLocales, options).
-    return supported_locales(global_object, requested_locales, options);
+    return TRY_OR_DISCARD(supported_locales(global_object, requested_locales, options));
 }
 
 }