How to disable downloading of sources.jar and javadoc.jar

I have configured as follows in app/build.gradle, but it not works. Can someone tell me how to disable download of sources and javadoc? The version of AndroidStudio is 4.0, and the grade plugin version is also 4.0.0

idea {
    module {
        downloadJavadoc = false

        downloadSources = false
    }
}