Bug 164989 [Viewers] ColumnViewer#getColumnViewerOwner() doesn't respects column count
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TreeViewer.java
} else {
					if (!item.getExpanded()) {
						item.setItemCount(1);
						TreeItem child = item.getItem(0);
						if (child.getData() != null) {
							disassociate(child);
						}
						item.clear(0, true);
					}
				}
		}
	}
	/**
	 * Update the widget at index.
	 * @param widget
	 * @param index
	 */
	private void virtualLazyUpdateWidget(Widget widget, int index) {
		if (contentProviderIsTreeBased) {
			TreePath treePath;
			if (widget instanceof Item) {
				treePath = getTreePathFromItem((Item) widget);
			} else {
				treePath = TreePath.EMPTY;
			}
			((ILazyTreePathContentProvider) getContentProvider())
					.updateElement(treePath, index);
		} else {
			((ILazyTreeContentProvider) getContentProvider()).updateElement(
					widget.getData(), index);