Bug 341273 ESS will not work without parts
While windows without any parts probably isn't a very interesting shape, it is still possible to create such a thing. In this scenario, the ESS may not work properly because we rely solely on the active part for selection information. It should be possible to have a selection at the window level as-is.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/internal/workbench/SelectionServiceImpl.java
*/
	public void setSelection(Object selection) {
		if (selection != null) {
			context.set(OUT_SELECTION, selection);
			if (activePart != null && activePart.getContext() == context) {
				serviceRoot.getContext().set(IServiceConstants.ACTIVE_SELECTION, selection);
			}
		} else {
			context.remove(OUT_SELECTION);
			if (activePart != null && activePart.getContext() == context) {
				serviceRoot.getContext().remove(IServiceConstants.ACTIVE_SELECTION);
			}
		}
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.e4.ui.selection.ESelectionService#getSelection()
	 */
	public Object getSelection() {
		if (activePart == null) {
			return null;
		}
		IEclipseContext partContext = activePart.getContext();
		return partContext == null ? null : partContext.get(ESelectionService.SELECTION);
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see