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/StructuredViewerManager.java
private Viewer viewer;
	private Object cachedOldInput;
	private Object cachedNewInput;
	
	private UIJob refreshJob = new UIJob(
			CommonNavigatorMessages.StructuredViewerManager_0) {
		public IStatus runInUIThread(IProgressMonitor monitor) {
			if(viewer != null) {
				try {
					if (viewer.getControl().isDisposed()) {
						return Status.OK_STATUS;
					}
					Display display = viewer.getControl().getDisplay();
					if (!display.isDisposed() && viewer != null) {
						viewer.refresh();
					}
				} catch (RuntimeException e) {
					NavigatorPlugin.logError(0, e.toString(), e);
				}
			}
			return Status.OK_STATUS;
		}
	};
	/**