Bug 15844 [Exception Handling] SelectionChange events and NPE
Build 20020508 Due to new global actions there are now more objects listening to selection changes send out by a JFace viewer. We now had the case that one of the listener generated a NPE. As a result all listeners registered after that one didn't receive the selection change event. StructuredViewers should be more fault tolorant to exceptions when informing listeners.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
}
	return null;
}
/**
 * Copies the attributes of the given element into the given SWT item.
 *
 * @param item the SWT item
 * @param element the element
 */
protected abstract void doUpdateItem(Item item, Object element);
/* (non-Javadoc)
 * Method declared on StructuredViewer.
 */
protected void doUpdateItem(Widget widget, Object element, boolean fullMap) {
	if (widget instanceof Item) {
		Item item = (Item) widget;
		
		if (fullMap) {
			Object data = widget.getData();
			if (data != null && data != element && data.equals(element)) {
				
				
				
				unmapElement(data, item);
				item.setData(element);
				mapElement(element, item);
			} else {
				
				associate(element, item);
			}