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
EPartService.class.getName());
		MPart part = partService.showPart("part",
				EPartService.PartState.VISIBLE);
		assertEquals(1, stack.getChildren().size());
		assertEquals(part, stack.getChildren().get(0));
		assertEquals(part, partService.getActivePart());
	}
	public void testShowPart_Id_VISIBLE5() {
		MApplication application = ApplicationFactoryImpl.eINSTANCE
				.createApplication();
		MWindow window = BasicFactoryImpl.eINSTANCE.createWindow();
		application.getChildren().add(window);
		MPartDescriptor partDescriptor = org.eclipse.e4.ui.model.application.descriptor.basic.impl.BasicFactoryImpl.eINSTANCE
				.createPartDescriptor();
		partDescriptor.setElementId("partB");
		partDescriptor.setCategory("aCategory");
		application.getDescriptors().add(partDescriptor);
		MPartStack partStack = BasicFactoryImpl.eINSTANCE.createPartStack();
		partStack.setElementId("aCategory");
		window.getChildren().add(partStack);
		MPart partA = BasicFactoryImpl.eINSTANCE.createPart();
		partA.setElementId("partA");
		partStack.getChildren().add(partA);
		MPart partB = BasicFactoryImpl.eINSTANCE.createPart();
		partB.setElementId("partB");
		partB.setToBeRendered(false);
		partStack.getChildren().add(partB);
		partStack.setSelectedElement(partA);
		window.setSelectedElement(partStack);
		application.setSelectedElement(window);