mapEachNotNull
inline fun <T, R : Any> Provider<Collection<T>>.mapEachNotNull(crossinline transform: (T) -> R?): Provider<List<R>>
Creates and returns a new Provider that maps each element of the Collection obtained from this using the transform function and filters out all null results.
transform should be a pure function.
The returned provider will only be stored in a WeakReference in the parent provider (this).