Bug 275929 [CommonNavigator] IPipelinedTreeContentProvider.getPipelinedElements() not ever called
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/internal/navigator/NavigatorContentServiceContentProvider.java
* expression &lt;enables&gt; statement of the
	 * <b>org.eclipse.ui.navigator.navigatorContent </b> extension point.
	 * </p>
	 * {@inheritDoc}
	 * 
	 * @param anElement
	 *            An element that requires its logical parent - generally as a
	 *            result of setSelection(expand=true) on the viewer
	 * @return The logical parent if available or null if the parent cannot be
	 *         determined
	 * @see org.eclipse.jface.viewers.ITreeContentProvider#getParent(java.lang.Object)
	 */
	public synchronized Object getParent(Object anElement) {
		contentService.resetContributionMemory();
		Set extensions = contentService
				.findContentExtensionsWithPossibleChild(anElement);
		Object parent;
		NavigatorContentExtension foundExtension;
		NavigatorContentExtension[] overridingExtensions;
		for (Iterator itr = extensions.iterator(); itr.hasNext();) {
			foundExtension = (NavigatorContentExtension) itr.next();
			try {
				if (!isOverridingExtensionInSet(foundExtension.getDescriptor(),
						extensions)) {
					parent = foundExtension.internalGetContentProvider().getParent(
							anElement);
					overridingExtensions = foundExtension
							.getOverridingExtensionsForPossibleChild(anElement);
					if (overridingExtensions.length > 0) {
						parent = pipelineParent(anElement,