Bug 167323 [Viewers]Open AbstractTreeViewer for external widget implementors
As reported by Ross Camara AbstractTreeViewer would work for nebula if we would open the API a bit. Boris and I decided that we will do this in 2 steps: 1. open the API 2. moving the Virtual-Support bits from TreeViewer to AbstractTreeViewer when the nebula grid provides virtual support.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
return;
		}
		Widget[] items = findItems(element);
		if (items.length != 0) {
			for (int i = 0; i < items.length; i++) {
				
				internalRefresh(items[i], element, true, updateLabels);
			}
		}
	}
	/**
	 * Refreshes the tree starting at the given widget.
	 * <p>
	 * EXPERIMENTAL. Not to be used except by JDT. This method was added to
	 * support JDT's explorations into grouping by working sets, which requires
	 * viewers to support multiple equal elements. See bug 76482 for more
	 * details. This support will likely be removed in Eclipse 3.2 in favour of
	 * proper support for multiple equal elements.
	 * </p>
	 * 
	 * @param widget
	 *            the widget
	 * @param element
	 *            the element
	 * @param doStruct
	 *            <code>true</code> if structural changes are to be picked up,
	 *            and <code>false</code> if only label provider changes are of
	 *            interest
	 * @param updateLabels
	 *            <code>true</code> to update labels for existing elements,