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
Widget item = internalExpand(element, false);
	if (item instanceof Item) {
		if (expanded) {
			createChildren(item);
		}
		setExpanded((Item) item, expanded);
	}
}
/**
 * Sets the selection to the given list of items.
 *
 * @param items list of items (element type: <code>org.eclipse.swt.widgets.Item</code>)
 */
protected abstract void setSelection(List items);
/* (non-Javadoc)
 * Method declared on StructuredViewer.
 */
protected void setSelectionToWidget(List v, boolean reveal) {
	if (v == null) {
		setSelection(new ArrayList(0));
		return;
	}
	int size = v.size();
	List newSelection = new ArrayList(size);
	for (int i = 0; i < size; ++i) {
		
		Widget w = internalExpand(v.get(i), true);
		if (w instanceof Item) {
			newSelection.add(w);
		}