Drop-down menu arrow too small.

[pyscripter]

TSpTBXItemViewer.Paint uses the following to paint the arrow of drop-down buttons:
SpDrawArrow(Canvas, P.X, P.Y, DropDownC, not ItemInfo.IsVertical, False, PPIScale(2));

The size of 2 results in too small an arrow:

A size of 4 (or maybe 3) looks better:

Both images are scaled 300%.

SpDrawArrow with a size of 2 is used in a few other places that could be reviewed.