Bug 327033 Workbench doesn't relayout after a stack disappears
If you close all the views of a stack, you just get an empty rectangle of space now. Resizing your window will adjust the layout properly. Note that reopening the views don't help, you still have to resize something to force a layout.
bundles/org.eclipse.e4.ui.workbench.swt/src/org/eclipse/e4/ui/internal/workbench/swt/PartRenderingEngine.java
context.set(intf.getName(), contextModel);
			populateModelInterfaces(contextModel, context, intf.getInterfaces());
		}
	}
	private String getContextName(MUIElement element) {
		StringBuilder builder = new StringBuilder(element.getClass()
				.getSimpleName());
		String elementId = element.getElementId();
		if (elementId != null && elementId.length() != 0) {
			builder.append(" (").append(elementId).append(") ");
		}
		builder.append("Context");
		return builder.toString();
	}
	public Object createGui(MUIElement element, Object parentWidget,
			IEclipseContext parentContext) {
		if (!element.isToBeRendered())
			return null;
		if (!renderedElements.contains(element))
			renderedElements.add(element);
		
		if (removeRoot != null) {
			return null;
		}
		if (element.getWidget() != null) {
			if (element.getWidget() instanceof Control
					&& parentWidget instanceof Composite) {
				Control ctrl = (Control) element.getWidget();
				if (ctrl.getParent() != parentWidget) {
					ctrl.setParent((Composite) parentWidget);