Bug 315281 update copyrights for 3.6
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/navigator/CommonViewerSorter.java
if (parentPath.getSegmentCount() == 0)
			return false;
		ViewerSorter sorter = sorterService.findSorter(contentDesc, parentPath.getLastSegment(), element, null);
		if (sorter != null)
			return sorter.isSorterProperty(element, property);
        return false;
    }
    
	private INavigatorContentDescriptor getSource(Object o) {
		
		INavigatorContentDescriptor ncd = contentService.getSourceOfContribution(o);
		if (ncd != null) {
			if (Policy.DEBUG_SORT)
				System.out.println("sort: " + ncd + " object: " + o); 
			return ncd;
		}
		Set descriptors = contentService.findDescriptorsByTriggerPoint(o, NavigatorContentService.CONSIDER_OVERRIDES);
		if (descriptors != null && descriptors.size() > 0) {
			ncd = (INavigatorContentDescriptor) descriptors.iterator().next();
			if (Policy.DEBUG_SORT)
				System.out.println("sort: " + ncd + " object: " + o); 
			return ncd;
		}
		if (Policy.DEBUG_SORT)
			System.out.println("sort: NULL object: " + o); 
		return null;
	}
	
}