When I updated to gradle 3.5 (and gsk 0.8 as a result), IDEA started showing this part of code in red, saying that the

ReobfTaskWrapper

class doesn't exist, why?

configure<NamedDomainObjectContainer<ReobfTaskFactory.ReobfTaskWrapper>> {
    create("shadowJar").apply {
       mappingType = ReobfMappingType.SEARGE
    }
}

The buildscript works just fine even with that.