Bug 260892 [CellEditors] NPE from ColumnViewerEditor caused by showing a dialog during modify
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/ColumnViewerEditor.java
control.addMouseListener(mouseListener);
				}
				if (tabeditingListener == null) {
					tabeditingListener = new TraverseListener() {
						public void keyTraversed(TraverseEvent e) {
							if ((feature & DEFAULT) != DEFAULT) {
								processTraverseEvent(cell.getColumnIndex(),
										viewer.getViewerRowFromItem(cell
												.getItem()), e);
							}
						}
					};
				}
				control.addTraverseListener(tabeditingListener);
				if (editorActivationListener != null
						&& !editorActivationListener.isEmpty()) {
					Object[] ls = editorActivationListener.getListeners();
					for (int i = 0; i < ls.length; i++) {
						((ColumnViewerEditorActivationListener) ls[i])
								.afterEditorActivated(activationEvent);
					}
				}
				
				this.cell.getItem().addDisposeListener(disposeListener);
				return true;
			}
		}
		return false;
	}
	private boolean shouldFireDoubleClick(int activationTime, int mouseTime,