we need this for our product which we'd like to release based on 1.8
currently there's no way to squish inline styles, and it's not convenient to
squish out of line styles. this api would enable squishing both.
Is this bug still valid? What does it have to do with content policies and ShouldProcess()?
Yes, and everything. Right now we don't call ShouldProcess for stylesheets.
Whether we should is unclear; I rather dislike the ShouldProcess API....