Bug 330803 SWTException from tool item dropdowns after closing/reopening perspectives
1. Click the 'Run' tool item's dropdown arrow. 2. Window > Close Perspective 3. Window > Open Perspective > Other... > Java 4. Repeat step 1. org.eclipse.swt.SWTException: Widget is disposed at org.eclipse.swt.SWT.error(SWT.java:4091) at org.eclipse.swt.SWT.error(SWT.java:4006) at org.eclipse.swt.SWT.error(SWT.java:3977) at org.eclipse.swt.widgets.Widget.error(Widget.java:468) at org.eclipse.swt.widgets.Widget.checkWidget(Widget.java:340) at org.eclipse.swt.widgets.Menu.setLocation(Menu.java:1427) at org.eclipse.e4.ui.workbench.renderers.swt.ToolItemRenderer$5.widgetSelected(ToolItemRenderer.java:315) at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:234) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1053) at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4084) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3675) at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$6.run(PartRenderingEngine.java:780) at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332) at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:696) at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:91)
bundles/org.eclipse.e4.ui.workbench.renderers.swt/src/org/eclipse/e4/ui/workbench/renderers/swt/ToolItemRenderer.java
}
			TriggerSequence sequence = bs.getBestSequenceFor(handledItem
					.getWbCommand());
			if (sequence != null) {
				if (text == null) {
					try {
						text = cmd.getName();
					} catch (NotDefinedException e) {
						return null;
					}
				}
				text = text + " (" + sequence.format() + ')'; 
			}
			return text;
		}
		return text;
	}
	public Object createWidget(final MUIElement element, Object parent) {
		if (!(element instanceof MToolItem) || !(parent instanceof ToolBar))
			return null;
		MToolItem itemModel = (MToolItem) element;
		
		int addIndex = calcVisibleIndex(element);
		
		MMenu menu = itemModel.getMenu();
		int flags = 0;
		if (menu != null) {
			flags |= SWT.DROP_DOWN;
		} else if (itemModel.getType() == ItemType.PUSH)
			flags |= SWT.PUSH;