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
window.getChildren().add(perspectiveStack);
		window.setSelectedElement(perspectiveStack);
		MPerspective perspectiveA = AdvancedFactoryImpl.eINSTANCE
				.createPerspective();
		perspectiveStack.getChildren().add(perspectiveA);
		perspectiveStack.setSelectedElement(perspectiveA);
		MPlaceholder placeholderA1 = AdvancedFactoryImpl.eINSTANCE
				.createPlaceholder();
		placeholderA1.setRef(partA);
		partA.setCurSharedRef(placeholderA1);
		perspectiveA.getChildren().add(placeholderA1);
		perspectiveA.setSelectedElement(placeholderA1);
		MPerspective perspectiveB = AdvancedFactoryImpl.eINSTANCE
				.createPerspective();
		perspectiveStack.getChildren().add(perspectiveB);
		MPartSashContainer partSashContainer = BasicFactoryImpl.eINSTANCE
				.createPartSashContainer();
		perspectiveB.getChildren().add(partSashContainer);
		perspectiveB.setSelectedElement(partSashContainer);
		MPlaceholder placeholderA2 = AdvancedFactoryImpl.eINSTANCE
				.createPlaceholder();
		placeholderA2.setRef(partA);
		perspectiveB.getChildren().add(placeholderA2);
		perspectiveB.setSelectedElement(placeholderA2);
		MPartStack partStack = BasicFactoryImpl.eINSTANCE.createPartStack();
		partSashContainer.getChildren().add(partStack);
		partSashContainer.setSelectedElement(partStack);
		MPart partB = BasicFactoryImpl.eINSTANCE.createPart();
		partStack.getChildren().add(partB);
		MPart partC = BasicFactoryImpl.eINSTANCE.createPart();