Github user bowenli86 commented on the issue:
https://github.com/apache/flink/pull/5356
@StefanRRichter I think how `null` is handled is one major benefit, not
all. Another benefit is that `iterator()` is more intuitive in traversing all
values. For example, this change makes ListState more similar to how MapState
handles traversing - In MapState, it has `values()` and `iterator()` that both
traverse entries in the map. ---
