Bug 172814 [Viewers] Rename AbstractViewerEditor to ColumnViewerEditor
There is no "AbstractViewer", and this class is referenced from ColumnViewer. To make the names more consistent, it should be called ColumnViewerEditor, not AbstractViewerEditor.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TreeViewer.java
* label text and image for each column. If it is an
	 * <code>ILabelProvider</code>, then it provides only the label text and
	 * image for the first column, and any remaining columns are blank.
	 */
	public IBaseLabelProvider getLabelProvider() {
		return super.getLabelProvider();
	}
	/*
	 * (non-Javadoc) Method declared in AbstractTreeViewer.
	 */
	protected Item getParentItem(Item item) {
		return ((TreeItem) item).getParentItem();
	}
	/*
	 * (non-Javadoc) Method declared in AbstractTreeViewer.
	 */
	protected Item[] getSelection(Control widget) {
		return ((Tree) widget).getSelection();
	}
	/**
	 * Returns this tree viewer's tree control.
	 * 
	 * @return the tree control
	 */
	public Tree getTree() {
		return tree;
	}
	/*
	 * (non-Javadoc)
	 *