Bug 139511 [CommonNavigator] getParent() fails in certain cases
In the implementation of getParents(), clients can sometimes fail to return the correct parent with the override cases taken into account. The attached patch fixes these issues, but should be reviewed by the Team Team to ensure that it does not cause any regressions for their cases.
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/internal/navigator/extensions/NavigatorContentDescriptor.java
private String name;
	private IConfigurationElement configElement;
	private int priority = Priority.NORMAL_PRIORITY_VALUE;
	private Expression enablement;
	private Expression possibleChildren;
	private String icon;
	private boolean activeByDefault;
	private IPluginContribution contribution;
	private Set overridingExtensions;
	private OverridePolicy overridePolicy;
	private String suppressedExtensionId;
	private INavigatorContentDescriptor overriddenDescriptor;
	private int hashCode;
	private boolean providesSaveables;
	/**
	 * Creates a new content descriptor from a configuration element.
	 * 
	 * @param configElement
	 *            configuration element to create a descriptor from
	 * 
	 * @throws WorkbenchException
	 *             if the configuration element could not be parsed. Reasons
	 *             include:
	 *             <ul>
	 *             <li>A required attribute is missing.</li>
	 *             <li>More elements are define than is allowed.</li>
	 *             </ul>
	 */
	 NavigatorContentDescriptor(IConfigurationElement configElement)
			throws WorkbenchException {