Bug 327044 EPartService's hidePart(*) should unset the part's parent element if the part is the selected element
It is not valid to have a selected element that's TBR flag is 'false'.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/internal/workbench/PartServiceImpl.java
List<MPart> dirtyPartsList = Collections.unmodifiableList(new ArrayList<MPart>(
					dirtyParts));
			Save[] decisions = saveHandler.promptToSave(dirtyPartsList);
			for (Save decision : decisions) {
				if (decision == Save.CANCEL) {
					return false;
				}
			}
			for (int i = 0; i < decisions.length; i++) {
				if (decisions[i] == Save.YES) {
					if (!savePart(dirtyPartsList.get(i), false)) {
						return false;
					}
				}
			}
			return true;
		}
		for (MPart dirtyPart : dirtyParts) {
			if (!savePart(dirtyPart, false)) {
				return false;
			}
		}
		return true;
	}
	private Collection<MInputPart> getInputParts() {
		return modelService.findElements(getContainer(), null, MInputPart.class, null);
	}
	public Collection<MInputPart> getInputParts(String inputUri) {
		Assert.isNotNull(inputUri, "Input uri must not be null"); 
		Collection<MInputPart> rv = new ArrayList<MInputPart>();