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
return part;
		case VISIBLE:
			if (activePart.getParent() != part.getParent()) {
				bringToTop(part);
			}
		}
		return part;
	}
	public MPart showPart(String id, PartState partState) {
		Assert.isNotNull(id);
		Assert.isNotNull(partState);
		MPart part = findPart(id);
		if (part != null) {
			return showPart(part, partState);
		}
		MPartDescriptor descriptor = findDescriptor(id);
		part = createPart(descriptor);
		if (part == null) {
			return null;
		}
		return showNewPart(part, partState);
	}
	public MPart showPart(MPart part, PartState partState) {
		Assert.isNotNull(part);
		Assert.isNotNull(partState);
		MPart localPart = findPart(part.getId());
		if (localPart != null) {
			return showExistingPart(partState, part, localPart);
		}
		return showNewPart(part, partState);