Bug 303801 IAE thrown when moving a part from one stack to another
1. Start the photo demo. 2. Move the 'Thumbnails' view to the stack of the 'Location' view. 3. An IAE is thrown. java.lang.IllegalArgumentException: Widget has the wrong parent at org.eclipse.swt.SWT.error(SWT.java:4064) at org.eclipse.swt.SWT.error(SWT.java:3998) at org.eclipse.swt.SWT.error(SWT.java:3969) at org.eclipse.swt.custom.CTabItem.setControl(CTabItem.java:283) at org.eclipse.e4.workbench.ui.renderers.swt.StackRenderer.createTab(StackRenderer.java:286) at org.eclipse.e4.workbench.ui.renderers.swt.StackRenderer.childRendered(StackRenderer.java:313) at org.eclipse.e4.ui.workbench.swt.internal.PartRenderingEngine$2.handleEvent(PartRenderingEngine.java:139) at org.eclipse.e4.ui.services.internal.events.UIEventHandler.handleEvent(UIEventHandler.java:41) at org.eclipse.equinox.internal.event.EventHandlerWrapper.handleEvent(EventHandlerWrapper.java:188) at org.eclipse.equinox.internal.event.EventHandlerTracker.dispatchEvent(EventHandlerTracker.java:198) at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:227) at org.eclipse.osgi.framework.eventmgr.ListenerQueue.dispatchEventSynchronous(ListenerQueue.java:149) at org.eclipse.equinox.internal.event.EventAdminImpl.dispatchEvent(EventAdminImpl.java:139) at org.eclipse.equinox.internal.event.EventAdminImpl.sendEvent(EventAdminImpl.java:78) at org.eclipse.equinox.internal.event.EventComponent.sendEvent(EventComponent.java:39) at org.eclipse.e4.ui.services.internal.events.EventBroker.send(EventBroker.java:73) at org.eclipse.e4.workbench.ui.internal.UIEventPublisher.notifyChanged(UIEventPublisher.java:58) at org.eclipse.emf.common.notify.impl.BasicNotifierImpl.eNotify(BasicNotifierImpl.java:280) at org.eclipse.emf.common.notify.impl.NotificationImpl.dispatch(NotificationImpl.java:1033) at org.eclipse.emf.common.notify.impl.NotificationImpl.dispatch(NotificationImpl.java:1038) at org.eclipse.emf.common.notify.impl.NotifyingListImpl.addUnique(NotifyingListImpl.java:305) at org.eclipse.emf.common.util.AbstractEList.add(AbstractEList.java:307) at org.eclipse.e4.workbench.ui.renderers.swt.dnd.DragHost.drop(DragHost.java:119) at org.eclipse.e4.workbench.ui.renderers.swt.dnd.DnDManager.endDrag(DnDManager.java:224) at org.eclipse.e4.workbench.ui.renderers.swt.dnd.DnDManager$2.handleEvent(DnDManager.java:73) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
bundles/org.eclipse.e4.ui.workbench.renderers.swt/src/org/eclipse/e4/workbench/ui/renderers/swt/dnd/DragHost.java
}
	public DragHost(MUIElement element) {
		assert (dragElement != null);
		dragElement = element;
		originalParent = dragElement.getParent();
		originalIndex = originalParent.getChildren().indexOf(element);
		baseWindow = getWindow();
		assert (baseWindow != null && baseWindow.getWidget() != null);
		attach();
	}
	public Shell getShell() {
		return (Shell) dragWindow.getWidget();
	}
	public MWindow getModel() {
		return dragWindow;
	}
	private MWindow getWindow() {
		MUIElement pe = originalParent;
		while (pe != null && !(pe instanceof MApplication)) {
			if (((Object) pe) instanceof MWindow)
				return (MWindow) pe;
			pe = pe.getParent();
		}
		return null;
	}
	private void attach() {
		Point size = new Point(200, 200);
		if (dragElement.getWidget() instanceof Control) {
			Control ctrl = (Control) dragElement.getWidget();
			size = ctrl.getSize();