Bug 328296 DND of markers views causes NPE in StackRenderer
bundles/org.eclipse.e4.ui.workbench.renderers.swt/src/org/eclipse/e4/ui/workbench/renderers/swt/StackRenderer.java
}
			public void widgetSelected(SelectionEvent e) {
				
				if (ignoreTabSelChanges)
					return;
				MUIElement ele = (MUIElement) e.item.getData(OWNING_ME);
				ele.getParent().setSelectedElement(ele);
				activateStack(stack);
			}
		});
		MouseListener mouseListener = new MouseAdapter() {
			@Override
			public void mouseUp(MouseEvent e) {
				if (e.button == 2) {
					CTabItem item = ctf.getItem(new Point(e.x, e.y));
					if (item != null) {
						closePart(item);
					}
				}
			}
		};
		ctf.addMouseListener(mouseListener);
		CTabFolder2Adapter closeListener = new CTabFolder2Adapter() {
			public void close(CTabFolderEvent event) {
				event.doit = closePart(event.item);
			}
		};
		ctf.addCTabFolder2Listener(closeListener);