GetFriendlyUrl returns null when indexing Search and Navigation for commerce content

[gatisb]

add extensions method to be indexed, something like this:

ContentIndexer.Instance.Conventions.ForInstancesOf<Product>().ShouldIndex(_ => true);
clientConventions.ForInstancesOf<Product>().IncludeField(x => x.MyMethodThatCallsGetFriendlyUrl());

have site configuration as follows:

Commerce content(products and also categories)
product.ContentLink.GetFriendlyUrl() returns null
product.ContentLink.GetFriendlyUrl(product.Language?.TwoLetterISOLanguageName) returns null
for all products/all languages when indexed using Search and Navigation indexing job

In other scheduled jobs this product.ContentLink.GetFriendlyUrl(product.Language?.TwoLetterISOLanguageName) does return correct Url.

While CMS content:
articlePage.ContentLink.GetFriendlyUrl(articlePage.Language?.TwoLetterISOLanguageName) returns correct Url in ALL scheduled jobs

Also maybe it would be good to have:
product.GetFriendlyUrl() so that no language is needed to be passed in when you have content already