Exploring what it would take for the 3DView Overlay stats to show **local** statistics. This patch seems to work, but might be done badly, not do enough, or just be too naive.
Once this patch is applied, you should see that the statusbar stats and the overlay stats can vary from each other. The following shows a workspace with three views, with the middle and right sides in local view
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This is done by adding an optional stats struct to View3D, to be used only when in localview. This way most views can share one copy of the stats, only need a unique version when necessary.