                         }
                         assert(rule != nil)
 
-                        result.fill()
+                        result.fill(())
                     }
                 }
             }

            let deferreds: [Deferred<Void>] = available.map { filename in
                let result = Deferred<Void>()
                ContentBlockerHelper.ruleStore.removeContentRuleList(forIdentifier: filename) { _ in
                   result.fill()
                }
                return result
            }

            let result = Deferred<Void>()
            ruleStore.lookUpContentRuleList(forIdentifier: filename) { contentRuleList, error in
                if contentRuleList != nil {
                    result.fill(())
                    return
                }
                loadJsonFromBundle(forResource: filename) { jsonString in
