Bug 337002 EPartService leaks previously active part
A reference is kept to the previously active part. This is unnecessary. We only need it to fire events. After the deactivation events have been fired, we should no longer need to keep it lying around.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/internal/workbench/PartServiceImpl.java
}
		return lastContainer;
	}
	private MElementContainer<?> getLastContainer(MElementContainer<?> container, List<?> children) {
		if (children.isEmpty()) {
			return null;
		}
		for (int i = children.size() - 1; i > -1; i--) {
			Object muiElement = children.get(i);
			if (muiElement instanceof MElementContainer<?>) {
				MElementContainer<?> childContainer = (MElementContainer<?>) muiElement;
				MElementContainer<?> lastContainer = getLastContainer(childContainer,
						childContainer.getChildren());
				if (lastContainer != null) {
					return lastContainer;
				}
			}
		}
		return container;
	}
	/**
	 * Returns the parent container of the specified element. If one cannot be found, a check will
	 * be performed to see whether the element is being represented by a placeholder, if it is, the
	 * placeholder's parent will be returned, if any.
	 * 
	 * @param element
	 *            the element to query
	 * @return the element's parent container, or the parent container of the specified element's
	 *         current placeholder, if it has one
	 */