Bug 166383 [Viewers] Provide Tabing from Editor to Editor
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractViewerEditor.java
if (control != null) {
				if (mouseListener != null) {
					control.removeMouseListener(mouseListener);
				}
				if (focusListener != null) {
					control.removeFocusListener(focusListener);
				}
			}
			c.deactivate();
		}
	}
	/**
	 * Cancle editing
	 */
	void cancelEditing() {
		if (cellEditor != null) {
			setEditor(null, null, 0);
			cellEditor.removeListener(cellEditorListener);
			CellEditor oldEditor = cellEditor;
			cellEditor = null;
			oldEditor.deactivate();
		}
	}
	/**
	 * Enable the editor by mouse down
	 * 
	 * @param event
	 */
	void handleMouseDown(MouseEvent event) {
		if (event.button != 1) {