App WorkerFactory setting for WorkManager sample

AppWorkerFactory.kt

class AppWorkerFactory @Inject constructor(
    private val workerFactories: Map<Class<out ListenableWorker>,
            @JvmSuppressWildcards Provider<ChildWorkerFactory>>
) : WorkerFactory() {
    override fun createWorker(
        appContext: Context,
        workerClassName: String,
        workerParameters: WorkerParameters
    ): ListenableWorker? {
        val foundEntry =
            workerFactories.entries.find { Class.forName(workerClassName).isAssignableFrom(it.key) }
        val factoryProvider = foundEntry?.value
            ?: throw IllegalArgumentException("unknown worker class name: $workerClassName")
        return factoryProvider.get().create(appContext, workerParameters)
    }
}