code: public static SanitizedContent fromSafeStyleSheetProto(SafeStyleSheetProto styleSheet) {
      return SanitizedContent.create(
          SafeStyleSheets.fromProto(styleSheet).getSafeStyleSheetString(), ContentKind.CSS);
    }
docs: Converts a {@link SafeStyleSheetProto} into a Soy {@link SanitizedContent} of kind CSS.