Fixes #3951. Adds View dependency to DimFunc and PosFunc

[BDisp]

Fixes

• Fixes NeedsLayout should automatically know when there's a View dependency (e.g. Dim.Func()) #3951

Proposed Changes/Todos

• Added DimFuncWithView with View dependency

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[BDisp]

View.EndInit only should call View.SetNeedsLayout and the Application.Begin should call LayoutAndDraw and PositionCursor. This avoid layout event run more than once and there is no need to Begin call Invoke because in the RunIteration the LayoutAndDraw and PositionCursor only run after the first Iteration event is raised.

[tig]

This is slick. Nice work.

I think it would be better if, instead of creating a new class for DimFuncWIthView, you instead added an optional View property to DimFunc and added another constuctor that took a View. Or made the existing DimFunc constructor take an optional View parameter.

[BDisp]

Done. I opted for add the optional View parameter and property because is impossible to store in a property two different types Func<int> and Func<View, int>. I was forgetting to also add this feature in the PosFunc. All done, I hope it's enough.