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/navigator/CommonNavigator.java
* Select Filters. Provides access to the "Select Filters" dialog that
	 * allows users to enable/disable filters and also the Content Extension
	 * activations.
	 * </p>
	 * </ul>
	 * 
	 * @return The Action Group to be associated with the Common Navigator View
	 *         Part.
	 */
	protected ActionGroup createCommonActionGroup() {
		return new CommonNavigatorActionGroup(this, commonViewer);
	}
	/**
	 * @return A listener to track the disposal of the Eclipse view part in
	 *         order to dispose of the framework state.
	 */
	protected DisposeListener createDisposeListener() {
		return new DisposeListener() {
			/**
			 * @see org.eclipse.swt.events.DisposeListener#widgetDisposed(org.eclipse.swt.events.DisposeEvent)
			 */
			public void widgetDisposed(DisposeEvent e) {
				dispose();
			}
		};
	}
	/**
	 * @return The initial input for the viewer. Defaults to
	 *         getSite().getPage().getInput()
	 */