Bug 327820 Active part stack is not highlighted in a newly opened perspective
1. Run on a new workspace. 2. Activate the 'Outline' view. 3. Window > Open Perspective > Debug 4. The 'Outline' view is active but its tab folder is not coloured blue.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/internal/workbench/PartServiceImpl.java
for (MWindow dw : win.getWindows()) {
					if (isInContainer(dw, element))
						return true;
				}
			}
		}
		if (container instanceof MWindow) {
			MWindow win = (MWindow) container;
			for (MWindow dw : win.getWindows()) {
				if (isInContainer(dw, element))
					return true;
			}
		}
		if (container instanceof MPerspective) {
			MPerspective persp = (MPerspective) container;
			for (MWindow dw : persp.getWindows()) {
				if (isInContainer(dw, element))
					return true;
			}
		}
		return false;
	}
	private MPlaceholder getLocalPlaceholder(MPart part) {
		return getLocalPlaceholder(getContainer(), part);
	}
	private MPlaceholder getLocalPlaceholder(MElementContainer<?> container, MPart part) {
		for (Object object : container.getChildren()) {
			if (object instanceof MElementContainer<?>) {
				MPlaceholder placeholder = getLocalPlaceholder((MElementContainer<?>) object, part);
				if (placeholder != null) {