Bug 172019 [Viewers] Plus sign doesn't disappear when using deferred content providers
3.3 M4 Use a tree viewer with a content provider using IDeferredWorkbenchAdapter and DeferredTreeContentManager. When fetchDeferredChildren is call and no elements are reported to the element collector the plus sign of the node doesn't disappear. This work without problems under Windows and Mac/OS (e.g. the plus sign disappears).
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
*            the parent item
	 * @param element
	 *            the element
	 * @return Widget
	 */
	private Widget internalFindItem(Item parent, Object element) {
		
		Object data = parent.getData();
		if (data != null) {
			if (equals(data, element)) {
				return parent;
			}
		}
		
		Item[] items = getChildren(parent);
		for (int i = 0; i < items.length; i++) {
			Item item = items[i];
			Widget o = internalFindItem(item, element);
			if (o != null) {
				return o;
			}
		}
		return null;
	}
	
	protected void internalRefresh(Object element) {
		internalRefresh(element, true);
	}
	
	protected void internalRefresh(Object element, boolean updateLabels) {