Bug 324839 Secondary part selected by EPS due to initially selected part being hidden and removed does not get rendered
1. Have a stack with two parts in it, the selected one has been rendered, the other one is not. 2. Hide the selected part using the EPS. 3. The other part is now the selected part, but it is not rendered.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/internal/workbench/PartServiceImpl.java
MElementContainer<MUIElement> parent = part.getParent();
			if (parent == null) {
				parent = modelService.findPlaceholderFor(getWindow(), part).getParent();
			}
			MUIElement oldSelectedElement = parent.getSelectedElement();
			modelService.bringToTop(getWindow(), part);
			if (oldSelectedElement != part && parent.getChildren().contains(part)
					&& parent instanceof MGenericStack<?>) {
				internalFixContext(part, oldSelectedElement);
			}
		}
	}
	private IEclipseContext getSubContext(MUIElement element) {
		if (element instanceof MContext) {
			return ((MContext) element).getContext();
		} else if (element instanceof MElementContainer<?>) {
			Object selectedElement = ((MElementContainer<?>) element).getSelectedElement();
			if (selectedElement instanceof MContext) {
				return ((MContext) selectedElement).getContext();
			} else if (selectedElement instanceof MElementContainer<?>) {
				return getSubContext((MUIElement) selectedElement);
			}
		}
		return null;
	}
	private void internalFixContext(MPart part, MUIElement oldSelectedElement) {
		if (oldSelectedElement == null) {
			return;
		}
		MContext parentPart = getParentWithContext(oldSelectedElement);