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
} else {
			item.setData(element);
			mapElement(element, item);
		}
		
		doUpdateItem(item,element);
	}
}
/**
 * Expands all nodes of the viewer's tree, starting with the root.
 * This method is equivalent to <code>expandToLevel(ALL_LEVELS)</code>.
 */
public void expandAll() {
	expandToLevel(ALL_LEVELS);
}
/**
 * Expands the root of the viewer's tree to the given level.
 *
 * @param level non-negative level, or <code>ALL_LEVELS</code> to expand
 *  all levels of the tree
 */
public void expandToLevel(int level) {
	expandToLevel(getRoot(), level);
}
/**
 * Expands all ancestors of the given element so that the given element
 * becomes visible in this viewer's tree control, and then expands the
 * subtree rooted at the given element to the given level.
 *
 * @param element the element