Bug 304074 View toolbars don't go away when the view is closed
1. Run the compatibility layer. 2. Close the 'Package Explorer' view. 3. Its toolbar is still there.
bundles/org.eclipse.e4.ui.workbench.renderers.swt/src/org/eclipse/e4/workbench/ui/renderers/swt/StackRenderer.java
if (part instanceof MPart && ((MPart) part).isCloseable()) {
			createFlags |= SWT.CLOSE;
		}
		
		int index = calcIndexFor(stack, part);
		cti = new CTabItem(ctf, createFlags, index);
		cti.setData(OWNING_ME, part);
		cti.setText(getLabel(itemPart, itemPart.getLabel()));
		cti.setImage(getImage(itemPart));
		cti.setToolTipText(itemPart.getTooltip());
		if (part.getWidget() != null)
			cti.setControl((Control) part.getWidget());
	}
	private int calcIndexFor(MElementContainer<MUIElement> stack,
			final MUIElement part) {
		int index = 0;
		
		for (MUIElement mPart : stack.getChildren()) {
			if (mPart == part)
				return index;
			if (mPart.isToBeRendered())
				index++;
		}
		return index;
	}
	@Override
	public void childRendered(
			final MElementContainer<MUIElement> parentElement,
			MUIElement element) {
		super.childRendered(parentElement, element);