Bug 282947 [CSS] ETabFolder does not draw right with border-visible: false
CTabFolders have always acted odd with respect to borders off and the first tab when selected. It just starts drawing top left. This behaviour seems to be confusing the ETabFolder draw code. It should draw the same curve regardless of whether borders are on or not.
bundles/org.eclipse.e4.ui.workbench.renderers.swt/src/org/eclipse/e4/workbench/ui/renderers/swt/StackModelFactory.java
Image viewMenuImage;
	@In
	IStylingEngine stylingEngine;
	public StackModelFactory() {
		super();
	}
	public Object createWidget(MPart<?> part, Object parent) {
		Widget newWidget = null;
		if (!(part instanceof MStack) || !(parent instanceof Composite))
			return null;
		Widget parentWidget = (Widget) parent;
		if (parentWidget instanceof Composite) {
			
			
			
			boolean showCloseAlways = false;
			int styleModifier = 0;
			if (part.getPolicy() != null && part.getPolicy().length() > 0) {
				String policy = part.getPolicy();
				if (policy.indexOf("ViewStack") >= 0) { 
					styleModifier = SWT.CLOSE;
				}
				if (policy.indexOf("EditorStack") >= 0) { 
					styleModifier = SWT.CLOSE;
					showCloseAlways = true;