Bug 282898 [CSS] ETabFolder should support background color behind tab area
Presently in CTabFolder, the unselected tab and the background color of the tab area are the same. We want them to be different. Not sure what property to use in CSS to support this, since background-color is presently used for the tabs themselves. One idea would be to make CTabItem be the element which supports color background-color :selected This would leave CTabFolder to interpret background color as the area behind the tabs.
bundles/org.eclipse.e4.ui.css.swt/src/org/eclipse/e4/ui/css/swt/properties/css2/CSSPropertyBackgroundSWTHandler.java
public String retrieveCSSPropertyBackgroundColor(Object element,
			String pseudo, CSSEngine engine) throws Exception {
		Widget widget = (Widget) element;
		Color color = null;
		if (widget instanceof CTabItem) {
			if ("selected".equals(pseudo)) {
				color = ((CTabItem) widget).getParent().getSelectionBackground();	
			} else {
				color = ((CTabItem) widget).getParent().getBackground();				
			}
		} else if (widget instanceof Control) {
			color = ((Control) widget).getBackground();	
		}
		return engine.convert(color, Color.class, null);
	}
	public String retrieveCSSPropertyBackgroundImage(Object widget,
			String pseudo, CSSEngine engine) throws Exception {
		
		return "none";
	}
	public String retrieveCSSPropertyBackgroundPosition(Object widget,
			String pseudo, CSSEngine engine) throws Exception {
		return null;
	}
	public String retrieveCSSPropertyBackgroundRepeat(Object widget,
			String pseudo, CSSEngine engine) throws Exception {
		return null;
	}
}