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/AbstractTableViewer.java
columnViewer.refresh(updateCell(getViewerRowFromItem(item),
						column));
				
				
				if (item.isDisposed()) {
					unmapElement(element, item);
					return;
				}
			}
		}
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.viewers.ColumnViewer#getColumnViewerOwner(int)
	 */
	protected Widget getColumnViewerOwner(int columnIndex) {
		if (columnIndex < 0
				|| (columnIndex > 0 && columnIndex >= doGetColumnCount())) {
			return null;
		}
		if (doGetColumnCount() == 0)
			return getControl();
		return doGetColumn(columnIndex);
	}
	/**
	 * Set the TableColumnViewerPart at columnIndex to be viewerPart.
	 * 
	 * @param viewerPart
	 * @param columnIndex