Update Pivot Location

This is done in:

GUnrealEd->UpdatePivotLocationForSelection(true);
UUnrealEdEngine::UpdatePivotLocationForSelection

But selection for spline points is different because they’re not UObjects, they have HSplineKeyProxy structs and this is updated in the FSplineComponentVisualizer::DrawVisualization. Selecting in the viewport calls FSplineComponentVisualizer::VisProxyHandleClick.