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
if (item instanceof Item) {
			if (expanded) {
				createChildren(item);
			}
			setExpanded((Item) item, expanded);
		}
	}
	/**
	 * Sets the selection to the given list of items.
	 * 
	 * @param items
	 *            list of items (element type:
	 *            <code>org.eclipse.swt.widgets.Item</code>)
	 */
	protected abstract void setSelection(List items);
	/**
	 * This implementation of setSelectionToWidget accepts a list of elements or
	 * a list of tree paths.
	 */
	protected void setSelectionToWidget(List v, boolean reveal) {
		if (v == null) {
			setSelection(new ArrayList(0));
			return;
		}
		int size = v.size();
		List newSelection = new ArrayList(size);
		for (int i = 0; i < size; ++i) {
			Object elementOrTreePath = v.get(i);