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.
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/application/EPartServiceTest.java
private IEclipseContext applicationContext;
	private IPresentationEngine engine;
	@Override
	protected void setUp() throws Exception {
		applicationContext = E4Application.createDefaultContext();
		super.setUp();
	}
	protected String getEngineURI() {
		return "platform:/plugin/org.eclipse.e4.ui.tests/org.eclipse.e4.ui.tests.application.HeadlessContextPresentationEngine"; 
	}
	@Override
	protected void tearDown() throws Exception {