Bug 164989 [Viewers] ColumnViewer#getColumnViewerOwner() doesn't respects column count
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TreeViewer.java
public void mouseDown(MouseEvent e) {
				treeViewerImpl.handleMouseDown(e);
			}
		});
		if ((treeControl.getStyle() & SWT.VIRTUAL) != 0) {
			treeControl.addDisposeListener(new DisposeListener() {
				public void widgetDisposed(DisposeEvent e) {
					treeIsDisposed = true;
					unmapAllElements();
				}
			});
			treeControl.addListener(SWT.SetData, new Listener() {
				public void handleEvent(Event event) {
					if (contentProviderIsLazy) {
						TreeItem item = (TreeItem) event.item;
						TreeItem parentItem = item.getParentItem();
						int index;
						if (parentItem != null) {
							index = parentItem.indexOf(item);
						} else {
							index = getTree().indexOf(item);
						}
						virtualLazyUpdateWidget(parentItem == null ? (Widget)getTree() : parentItem, index);
					}
				}
			});
		}
	}
	/**
	 * Initializes the tree viewer implementation.