Bug 329482 Uninstantiated part may be rendered when closing another part in the same stack
1. Activate the 'Javadoc' view. 2. Activate the 'Package Explorer' view. 3. Shutdown. 4. Restart. 5. Ctrl+3 > Properties 6. Hide the 'Properties' view. 7. Now the 'Problems' view is the selected element. It should be the 'Javadoc' view.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/internal/workbench/PartActivationHistory.java
return candidate == null ? getActivationCandidate(part) : candidate;
	}
	void forget(MWindow window, MPart part, boolean full) {
		if (full) {
			generalActivationHistory.remove(part);
		} else {
			for (MPlaceholder placeholder : modelService.findElements(window, null,
					MPlaceholder.class, null)) {
				
				if (placeholder.getRef() == part && placeholder.isToBeRendered()) {
					return;
				}
			}
			generalActivationHistory.remove(part);
		}
	}
	MPart getActivationCandidate(MPerspective perspective) {
		for (MPart candidate : generalActivationHistory) {
			if (partService.isInContainer(perspective, candidate)
					&& isValid(perspective, candidate)) {
				return candidate;
			}
		}
		Collection<MPart> candidates = perspective.getContext().get(EPartService.class).getParts();
		for (MPart candidate : candidates) {
			if (isValid(perspective, candidate)) {
				return candidate;
			}
		}
		return null;