Bug 303305 EPS cannot handle being asked for from the application's context
Right now we have this... @Inject @Named(EPartService.PART_SERVICE_ROOT) private MElementContainer<MUIElement> rootContainer; ...which will be 'null' if the question was posed to the application's context. Right now, I cannot use EPS in the SaveHandler because I get an (effectively) useless EPartService (filled with null fields).
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/workbench/ui/internal/PartServiceImpl.java
public void removePartListener(IPartListener listener) {
		listeners.remove(listener);
	}
	private MContext getParentWithContext(MUIElement part) {
		MElementContainer<MUIElement> parent = part.getParent();
		while (parent != null) {
			if (parent instanceof MContext) {
				if (((MContext) parent).getContext() != null)
					return (MContext) parent;
			}
			parent = parent.getParent();
		}
		return null;
	}
	public void bringToTop(MPart part) {
		if (isInContainer(part)) {
			part.setToBeRendered(true);
			internalBringToTop(part);
		}
	}
	private void internalBringToTop(MPart part) {
		MElementContainer<MUIElement> parent = part.getParent();
		MPart oldSelectedElement = (MPart) parent.getSelectedElement();
		if (oldSelectedElement != part) {
			parent.setSelectedElement(part);
			internalFixContext(part, oldSelectedElement);
		}
	}
	private void internalFixContext(MPart part, MPart oldSelectedElement) {
		MContext parentPart = getParentWithContext(oldSelectedElement);