Bug 317180 Screen cheese when starting fresh workspace
bundles/org.eclipse.e4.ui.workbench.renderers.swt/src/org/eclipse/e4/ui/workbench/renderers/swt/CTabRendering.java
@Optional
	public void setActiveToolbarGradient(
			@Named("activeToolbarColors") Color[] color,
			@Named("activeToolbarPercents") int[] percents) {
		activeToolbar = color;
		activePercents = percents;
	}
	@Inject
	@Optional
	public void setInactiveToolbarGradient(
			@Named("inactiveToolbarColors") Color[] color,
			@Named("inactiveToolbarPercents") int[] percents) {
		inactiveToolbar = color;
		inactivePercents = percents;
	}
	public void setActive(boolean active) {
		this.active = active;
		Control topRight = parent.getTopRight();
		if (topRight != null) {
			if (active && toolbarActiveImage == null)
				createActiveToolbarImages(Display.getCurrent());
			if (!active && toolbarInactiveImage == null)
				createInactiveToolbarImages(Display.getCurrent());
			topRight.setBackgroundImage(active ? toolbarActiveImage
					: toolbarInactiveImage);
			parent.redraw();
		}
	}
}