Shared flavor config

flavors.gradle

ext.flavorConfig = { // 1

    flavorDimensions "pricing"
    productFlavors {
        free {
            dimension "pricing"
            ext.myApplicationIdSuffix = '.free' // 2
        }
        paid {
            dimension "pricing"
            ext.myApplicationIdSuffix = '.paid'
        }
    }

    productFlavors.all { flavor -> // 3
        if (flavor.hasProperty('myApplicationIdSuffix') && isApplicationProject()) {
            flavor.applicationIdSuffix = flavor.myApplicationIdSuffix
        }
    }

}

def isApplicationProject() { // 4
    return project.android.class.simpleName.startsWith('BaseAppModuleExtension')
    // in AGP 3.1.x with library modules instead of feature modules:
    // return project.android instanceof com.android.build.gradle.AppExtension
}