Bug 307747 EPartService doesn't render new parts
1. Have a part in a stack, it is the selected part. 2. Show another part in that stack using PartState.CREATE or PartState.VISIBLE. 3. The part should've been rendered. It is not.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/workbench/ui/internal/PartServiceImpl.java
}
		return container;
	}
	private MPart showExistingPart(PartState partState, MPart providedPart, MPart localPart) {
		MPart part = addPart(providedPart, localPart);
		switch (partState) {
		case ACTIVATE:
			activate(part);
			return part;
		case VISIBLE:
			MPart activePart = getActivePart();
			if (activePart == null) {
				bringToTop(part);
			} else if (activePart.getParent() == part.getParent()) {
				
				part.setToBeRendered(true);
				engine.createGui(part);
			} else {
				bringToTop(part);
			}
			return part;
		case CREATE:
			part.setToBeRendered(true);
			engine.createGui(part);
			return part;
		}
		return part;
	}
	private MPart showNewPart(MPart part, PartState partState) {
		part = addPart(part, part);