Bug 325836 EPartService's createSharedPart(*) methods should not need its MWindow parameter
The service should only be interacting with its own window and not some other random window.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/internal/workbench/PartServiceImpl.java
*         current placeholder, if it has one
	 */
	private MElementContainer<MUIElement> getParent(MUIElement element) {
		MElementContainer<MUIElement> parent = element.getParent();
		if (parent == null) {
			MPlaceholder placeholder = element.getCurSharedRef();
			if (placeholder == null) {
				MElementContainer<MUIElement> container = getContainer();
				return findContainer(container, element);
			}
			return placeholder.getParent();
		}
		return parent;
	}
	private MElementContainer<MUIElement> findContainer(MElementContainer<?> container,
			MUIElement element) {
		for (Object child : container.getChildren()) {
			if (child == element) {
				return (MElementContainer<MUIElement>) container;
			} else if (child instanceof MPlaceholder) {
				MPlaceholder placeholder = (MPlaceholder) child;
				MUIElement ref = placeholder.getRef();
				if (ref == element) {
					return (MElementContainer<MUIElement>) container;
				} else if (ref instanceof MElementContainer<?>) {
					MElementContainer<MUIElement> match = findContainer((MElementContainer<?>) ref,
							element);
					if (match != null) {
						return match;
					}