@Override
	public Color getDefaultBackgroundColor() {
		return primaryModel.getDefaultBackgroundColor();
	}
Class for blending two {@link ListingBackgroundColorModel}s.  If neither model has a color
different from its default, then the primary's color is returned.  If only one model
has a color different from its default, then that color is returned.  If they both have
colors different, the color returned is a blend of the two colors.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/codebrowser/LayeredColorModel.java