Bug 329482 Uninstantiated part may be rendered when closing another part in the same stack
1. Activate the 'Javadoc' view. 2. Activate the 'Package Explorer' view. 3. Shutdown. 4. Restart. 5. Ctrl+3 > Properties 6. Hide the 'Properties' view. 7. Now the 'Problems' view is the selected element. It should be the 'Javadoc' view.
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/application/EPartServiceTest.java
}
			activated++;
			activatedParts.add(part);
		}
		public void partBroughtToTop(MPart part) {
		}
		public void partDeactivated(MPart part) {
			if (valid && part == null) {
				valid = false;
			}
			deactivated++;
			deactivatedParts.add(part);
		}
		public void partHidden(MPart part) {
			if (valid && part == null) {
				valid = false;
			}
			hidden++;
			hiddenParts.add(part);
		}
		public void partVisible(MPart part) {
			if (valid && part == null) {
				valid = false;
			}
			visible++;
			visibleParts.add(part);
		}
	}
}