Bug 327825 Activated part in current perspective has its tab item granted focus when switching perspectives
1. Activate the 'Outline' view. 2. Window > Open Perspective > Debug 3. The tab item of the 'Outline' view gets focus.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/internal/workbench/PartServiceImpl.java
MPartDescriptor descriptor = findDescriptor(id);
			sharedPart = createPart(descriptor);
			if (sharedPart == null) {
				return null;
			}
			sharedWindow.getSharedElements().add(sharedPart);
		}
		return createSharedPart(sharedPart);
	}
	private MPlaceholder createSharedPart(MPart sharedPart) {
		
		MPlaceholder sharedPartRef = AdvancedFactoryImpl.eINSTANCE.createPlaceholder();
		sharedPartRef.setElementId(sharedPart.getElementId());
		sharedPartRef.setRef(sharedPart);
		return sharedPartRef;
	}
	private MPart addPart(MPart providedPart, MPart localPart) {
		
		if (providedPart == localPart && isInContainer(providedPart)) {
			return providedPart;
		}
		MPartDescriptor descriptor = findDescriptor(providedPart.getElementId());
		if (descriptor == null) {
			if (!isInContainer(providedPart)) {
				adjustPlaceholder(providedPart);
				MPartStack stack = BasicFactoryImpl.eINSTANCE.createPartStack();
				MPlaceholder placeholder = providedPart.getCurSharedRef();
				if (placeholder != null) {
					stack.getChildren().add(placeholder);
				} else {