Bug 67890 [PropertiesView] Exception when entries added to properties view
bundles/org.eclipse.ui.views/src/org/eclipse/ui/views/properties/PropertySheetViewer.java
public void mouseDown(MouseEvent event) {
                
                Point pt = new Point(event.x, event.y);
                TreeItem item = tree.getItem(pt);
                if (item != null) {
                    handleSelect(item);
                }
            }
        });
        
        
        tree.addTreeListener(new TreeListener() {
            public void treeExpanded(final TreeEvent event) {
                handleTreeExpand(event);
            }
            public void treeCollapsed(final TreeEvent event) {
                handleTreeCollapse(event);
            }
        });
        
        tree.addKeyListener(new KeyAdapter() {
            public void keyReleased(KeyEvent e) {
                if (e.character == SWT.ESC)
                    deactivateCellEditor();
                else if (e.keyCode == SWT.F5)
                    
                    setInput(getInput());
            }
        });
    }