Bug 174701 [Viewers] ViewerRow should be reused instead of connected to the Item
Currently we create a ViewerRow ver every Item we create this can degrade performance, we should cache the row and reuse it
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/ColumnViewerEditor.java
void removeEditorActivationListener(
			ColumnViewerEditorActivationListener listener) {
		if (editorActivationListener != null) {
			editorActivationListener.remove(listener);
		}
	}
	/**
	 * Process the travers event and opens the next available editor depending
	 * of the implemented strategy. The default implementation uses the style
	 * constants
	 * <ul>
	 * <li>{@link ColumnViewerEditor#TABBING_MOVE_TO_ROW_NEIGHBOR}</li>
	 * <li>{@link ColumnViewerEditor#TABBING_CYCLE_IN_ROW}</li>
	 * <li>{@link ColumnViewerEditor#TABBING_VERTICAL}</li>
	 * <li>{@link ColumnViewerEditor#TABBING_HORIZONTAL}</li>
	 * </ul>
	 * 
	 * <p>
	 * Subclasses may overwrite to implement their custom logic to edit the next
	 * cell
	 * </p>
	 * 
	 * @param columnIndex
	 *            the index of the current column
	 * @param row
	 *            the current row
	 * @param event
	 *            the travers event
	 */
	protected void processTraverseEvent(int columnIndex, ViewerRow row,