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;
		}
		for (int i = 0; i < elements.length; i++) {
			boolean newItem = true;
			Object element = elements[i];
			int index;
			if (comparator == null) {
				if (itemExists(items, element)) {
					refresh(element);
					newItem = false;
				}
				index = -1;
			} else {
				lastInsertion = insertionPosition(items, comparator,
						lastInsertion, element, parentPath);
				
				
				if (lastInsertion == items.length) {
					index = -1;
				} else {
					while (lastInsertion < items.length
							&& internalCompare(comparator, parentPath, element,
									items[lastInsertion].getData()) == 0) {
						
						
						
						
						if (items[lastInsertion].getData().equals(element)) {