Bug 161401 [Viewers] Tweak ColumnViewer-API
- Rename getRowPart(Point point) => getViewerRow() - Rename getCell(Point point) => getViewerCell() - Rename setViewerColumn(final int columnIndex, ViewerColumn viewer) => setupEditingSupport - Make setupEditingSupport() private no one from external needs to use this API to set the EditingSupport for an ViewerColumn
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TreeViewer.java
disassociate(item);
						}
						item.dispose();
					}
				} else {
					Widget[] parentItems = internalFindItems(parentOrTreePath);
					for (int i = 0; i < parentItems.length; i++) {
						TreeItem parentItem = (TreeItem) parentItems[i];
						if (index < parentItem.getItemCount()) {
							TreeItem item = parentItem.getItem(index);
							if (item.getData() != null) {
								disassociate(item);
							}
							item.dispose();
						}
					}
				}
			}
		});
	}
	
	/* (non-Javadoc)
	 * @see org.eclipse.jface.viewers.AbstractTreeViewer#handleTreeExpand(org.eclipse.swt.events.TreeEvent)
	 */
	protected void handleTreeExpand(TreeEvent event) {
		if (contentProviderIsLazy) {
			if (event.item.getData() != null) {
				Item[] children = getChildren(event.item);
				if (children.length == 1 && children[0].getData()==null) {