Form is submitting on every re-render

[FrancoisCossette]

Using ComponentWithFormTrait, I notice that every re-render of the form submits it thanks to it's submitFormOnRender function and this seems to be intentionally mandatory.

I have some FormEvents that listen to Submit events to process the submitted data, and they are not liking this. Since I'm setting some fields as required, I expect them to be submitted with that, but now they are receiving some empty data on every re-render.

It seem to me that the only way to fix this is to make sure that my events can handle missing data, even when it's required data. Is this really the only way, or am I missing something?